diff --git a/packages/babel-generator/test/fixtures/flow/iterator-inside-declare/input.js b/packages/babel-generator/test/fixtures/flow/iterator-inside-declare/input.js
new file mode 100644
index 0000000000..5988be7988
--- /dev/null
+++ b/packages/babel-generator/test/fixtures/flow/iterator-inside-declare/input.js
@@ -0,0 +1,7 @@
+declare class A {
+  @@iterator(): Iterator<File>;
+}
+
+declare class A {
+  @@asyncIterator(): Iterator<File>;
+}
diff --git a/packages/babel-generator/test/fixtures/flow/iterator-inside-declare/output.js b/packages/babel-generator/test/fixtures/flow/iterator-inside-declare/output.js
new file mode 100644
index 0000000000..f140cac1a2
--- /dev/null
+++ b/packages/babel-generator/test/fixtures/flow/iterator-inside-declare/output.js
@@ -0,0 +1,6 @@
+declare class A {
+  @@iterator(): Iterator<File>
+}
+declare class A {
+  @@asyncIterator(): Iterator<File>
+}
\ No newline at end of file
diff --git a/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/input.js b/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/input.js
new file mode 100644
index 0000000000..dab9a962ac
--- /dev/null
+++ b/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/input.js
@@ -0,0 +1,7 @@
+interface A {
+  @@iterator(): Iterator<File>;
+}
+
+interface A {
+  @@asyncIterator(): Iterator<File>;
+}
diff --git a/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/output.js b/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/output.js
new file mode 100644
index 0000000000..ef726ab2fc
--- /dev/null
+++ b/packages/babel-generator/test/fixtures/flow/iterator-inside-interface/output.js
@@ -0,0 +1,6 @@
+interface A {
+  @@iterator(): Iterator<File>
+}
+interface A {
+  @@asyncIterator(): Iterator<File>
+}
\ No newline at end of file
diff --git a/packages/babel-generator/test/fixtures/flow/iterator-inside-types/input.js b/packages/babel-generator/test/fixtures/flow/iterator-inside-types/input.js
new file mode 100644
index 0000000000..a97778edc8
--- /dev/null
+++ b/packages/babel-generator/test/fixtures/flow/iterator-inside-types/input.js
@@ -0,0 +1,3 @@
+function foo(): { @@iterator: () => string } {
+  return (0: any);
+}
diff --git a/packages/babel-generator/test/fixtures/flow/iterator-inside-types/output.js b/packages/babel-generator/test/fixtures/flow/iterator-inside-types/output.js
new file mode 100644
index 0000000000..42fc4f9473
--- /dev/null
+++ b/packages/babel-generator/test/fixtures/flow/iterator-inside-types/output.js
@@ -0,0 +1,5 @@
+function foo(): {
+  @@iterator: () => string
+} {
+  return (0: any);
+}
\ No newline at end of file
diff --git a/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-iterator/input.js b/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-iterator/input.js
new file mode 100644
index 0000000000..741c23987d
--- /dev/null
+++ b/packages/babel-plugin-transform-flow-strip-types/test/fixtures/strip-types/strip-iterator/input.js
@@ -0,0 +1,15 @@
+declare class A {
+  @@iterator(): Iterator<File>;
+}
+
+declare class A {
+  @@asyncIterator(): Iterator<File>;
+}
+
+interface A {
+  @@iterator(): Iterator<File>;
+}
+
+interface A {
+  @@asyncIterator(): Iterator<File>;
+}
diff --git a/packages/babylon/src/plugins/flow.js b/packages/babylon/src/plugins/flow.js
index 7981df789a..b5c904ef19 100644
--- a/packages/babylon/src/plugins/flow.js
+++ b/packages/babylon/src/plugins/flow.js
@@ -8,6 +8,7 @@ import * as N from "../types";
 import type { Pos, Position } from "../util/location";
 import type State from "../tokenizer/state";
 import * as charCodes from "charcodes";
+import { isIteratorStart } from "../util/identifier";
 
 const primitiveTypes = [
   "any",
@@ -1626,8 +1627,12 @@ export default (superClass: Class<Parser>): Class<Parser> =>
 
     // ensure that inside flow types, we bypass the jsx parser plugin
     readToken(code: number): void {
+      const next = this.input.charCodeAt(this.state.pos + 1);
       if (this.state.inType && (code === 62 || code === 60)) {
         return this.finishOp(tt.relational, 1);
+      } else if (isIteratorStart(code, next)) {
+        this.state.isIterator = true;
+        return super.readWord(code);
       } else {
         return super.readToken(code);
       }
diff --git a/packages/babylon/src/tokenizer/context.js b/packages/babylon/src/tokenizer/context.js
index 49393869a0..11fe53d2d2 100644
--- a/packages/babylon/src/tokenizer/context.js
+++ b/packages/babylon/src/tokenizer/context.js
@@ -73,6 +73,9 @@ tt.name.updateContext = function(prevType) {
       this.state.exprAllowed = true;
     }
   }
+  if (this.state.isIterator) {
+    this.state.isIterator = false;
+  }
 };
 
 tt.braceL.updateContext = function(prevType) {
diff --git a/packages/babylon/src/tokenizer/index.js b/packages/babylon/src/tokenizer/index.js
index b6b8fdc501..3fce132907 100644
--- a/packages/babylon/src/tokenizer/index.js
+++ b/packages/babylon/src/tokenizer/index.js
@@ -1240,6 +1240,8 @@ export default class Tokenizer extends LocationParser {
       const ch = this.fullCharCodeAtPos();
       if (isIdentifierChar(ch)) {
         this.state.pos += ch <= 0xffff ? 1 : 2;
+      } else if (this.state.isIterator && ch === charCodes.atSign) {
+        this.state.pos += 1;
       } else if (ch === charCodes.backslash) {
         this.state.containsEsc = true;
 
@@ -1271,6 +1273,10 @@ export default class Tokenizer extends LocationParser {
     return word + this.input.slice(chunkStart, this.state.pos);
   }
 
+  isIterator(word): boolean {
+    return word === "@@iterator" || word === "@@asyncIterator";
+  }
+
   // Read an identifier or keyword token. Will check for reserved
   // words when necessary.
 
@@ -1286,6 +1292,14 @@ export default class Tokenizer extends LocationParser {
       type = keywordTypes[word];
     }
 
+    // Allow @@iterator and @@asyncIterator as a identifier only inside type
+    if (
+      this.state.isIterator &&
+      (!this.isIterator(word) || !this.state.inType)
+    ) {
+      this.raise(this.state.pos, `Invalid identifier ${word}`);
+    }
+
     this.finishToken(type, word);
   }
 
diff --git a/packages/babylon/src/util/identifier.js b/packages/babylon/src/util/identifier.js
index 15c2dd1971..de5ccb0bcb 100644
--- a/packages/babylon/src/util/identifier.js
+++ b/packages/babylon/src/util/identifier.js
@@ -87,6 +87,12 @@ export function isIdentifierStart(code: number): boolean {
   return isInAstralSet(code, astralIdentifierStartCodes);
 }
 
+// Test whether a current state character code and next character code  is @
+
+export function isIteratorStart(current: number, next: number): boolean {
+  return current === 64 && next === 64;
+}
+
 // Test whether a given character is part of an identifier.
 
 export function isIdentifierChar(code: number): boolean {
diff --git a/packages/babylon/test/fixtures/flow/iterator/01/input.js b/packages/babylon/test/fixtures/flow/iterator/01/input.js
new file mode 100644
index 0000000000..cc20f143c5
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/01/input.js
@@ -0,0 +1,3 @@
+declare class A {
+  @@iterator(): Iterator<File>;
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/01/output.json b/packages/babylon/test/fixtures/flow/iterator/01/output.json
new file mode 100644
index 0000000000..c8b579bc72
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/01/output.json
@@ -0,0 +1,225 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 51,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 3,
+      "column": 1
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 51,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 3,
+        "column": 1
+      }
+    },
+    "sourceType": "module",
+    "body": [
+      {
+        "type": "DeclareClass",
+        "start": 0,
+        "end": 51,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 1
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 14,
+          "end": 15,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 14
+            },
+            "end": {
+              "line": 1,
+              "column": 15
+            },
+            "identifierName": "A"
+          },
+          "name": "A"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 16,
+          "end": 51,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 16
+            },
+            "end": {
+              "line": 3,
+              "column": 1
+            }
+          },
+          "callProperties": [],
+          "properties": [
+            {
+              "type": "ObjectTypeProperty",
+              "start": 20,
+              "end": 48,
+              "loc": {
+                "start": {
+                  "line": 2,
+                  "column": 2
+                },
+                "end": {
+                  "line": 2,
+                  "column": 30
+                }
+              },
+              "key": {
+                "type": "Identifier",
+                "start": 20,
+                "end": 30,
+                "loc": {
+                  "start": {
+                    "line": 2,
+                    "column": 2
+                  },
+                  "end": {
+                    "line": 2,
+                    "column": 12
+                  },
+                  "identifierName": "@@iterator"
+                },
+                "name": "@@iterator"
+              },
+              "static": false,
+              "kind": "init",
+              "method": true,
+              "value": {
+                "type": "FunctionTypeAnnotation",
+                "start": 20,
+                "end": 48,
+                "loc": {
+                  "start": {
+                    "line": 2,
+                    "column": 2
+                  },
+                  "end": {
+                    "line": 2,
+                    "column": 30
+                  }
+                },
+                "params": [],
+                "rest": null,
+                "typeParameters": null,
+                "returnType": {
+                  "type": "GenericTypeAnnotation",
+                  "start": 34,
+                  "end": 48,
+                  "loc": {
+                    "start": {
+                      "line": 2,
+                      "column": 16
+                    },
+                    "end": {
+                      "line": 2,
+                      "column": 30
+                    }
+                  },
+                  "typeParameters": {
+                    "type": "TypeParameterInstantiation",
+                    "start": 42,
+                    "end": 48,
+                    "loc": {
+                      "start": {
+                        "line": 2,
+                        "column": 24
+                      },
+                      "end": {
+                        "line": 2,
+                        "column": 30
+                      }
+                    },
+                    "params": [
+                      {
+                        "type": "GenericTypeAnnotation",
+                        "start": 43,
+                        "end": 47,
+                        "loc": {
+                          "start": {
+                            "line": 2,
+                            "column": 25
+                          },
+                          "end": {
+                            "line": 2,
+                            "column": 29
+                          }
+                        },
+                        "typeParameters": null,
+                        "id": {
+                          "type": "Identifier",
+                          "start": 43,
+                          "end": 47,
+                          "loc": {
+                            "start": {
+                              "line": 2,
+                              "column": 25
+                            },
+                            "end": {
+                              "line": 2,
+                              "column": 29
+                            },
+                            "identifierName": "File"
+                          },
+                          "name": "File"
+                        }
+                      }
+                    ]
+                  },
+                  "id": {
+                    "type": "Identifier",
+                    "start": 34,
+                    "end": 42,
+                    "loc": {
+                      "start": {
+                        "line": 2,
+                        "column": 16
+                      },
+                      "end": {
+                        "line": 2,
+                        "column": 24
+                      },
+                      "identifierName": "Iterator"
+                    },
+                    "name": "Iterator"
+                  }
+                }
+              },
+              "optional": false
+            }
+          ],
+          "indexers": [],
+          "exact": false
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babylon/test/fixtures/flow/iterator/02/input.js b/packages/babylon/test/fixtures/flow/iterator/02/input.js
new file mode 100644
index 0000000000..48ecd5cb3d
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/02/input.js
@@ -0,0 +1,3 @@
+declare class A {
+  @@asyncIterator(): Iterator<File>;
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/02/output.json b/packages/babylon/test/fixtures/flow/iterator/02/output.json
new file mode 100644
index 0000000000..0b5dd41ee4
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/02/output.json
@@ -0,0 +1,225 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 56,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 3,
+      "column": 1
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 56,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 3,
+        "column": 1
+      }
+    },
+    "sourceType": "module",
+    "body": [
+      {
+        "type": "DeclareClass",
+        "start": 0,
+        "end": 56,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 1
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 14,
+          "end": 15,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 14
+            },
+            "end": {
+              "line": 1,
+              "column": 15
+            },
+            "identifierName": "A"
+          },
+          "name": "A"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 16,
+          "end": 56,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 16
+            },
+            "end": {
+              "line": 3,
+              "column": 1
+            }
+          },
+          "callProperties": [],
+          "properties": [
+            {
+              "type": "ObjectTypeProperty",
+              "start": 20,
+              "end": 53,
+              "loc": {
+                "start": {
+                  "line": 2,
+                  "column": 2
+                },
+                "end": {
+                  "line": 2,
+                  "column": 35
+                }
+              },
+              "key": {
+                "type": "Identifier",
+                "start": 20,
+                "end": 35,
+                "loc": {
+                  "start": {
+                    "line": 2,
+                    "column": 2
+                  },
+                  "end": {
+                    "line": 2,
+                    "column": 17
+                  },
+                  "identifierName": "@@asyncIterator"
+                },
+                "name": "@@asyncIterator"
+              },
+              "static": false,
+              "kind": "init",
+              "method": true,
+              "value": {
+                "type": "FunctionTypeAnnotation",
+                "start": 20,
+                "end": 53,
+                "loc": {
+                  "start": {
+                    "line": 2,
+                    "column": 2
+                  },
+                  "end": {
+                    "line": 2,
+                    "column": 35
+                  }
+                },
+                "params": [],
+                "rest": null,
+                "typeParameters": null,
+                "returnType": {
+                  "type": "GenericTypeAnnotation",
+                  "start": 39,
+                  "end": 53,
+                  "loc": {
+                    "start": {
+                      "line": 2,
+                      "column": 21
+                    },
+                    "end": {
+                      "line": 2,
+                      "column": 35
+                    }
+                  },
+                  "typeParameters": {
+                    "type": "TypeParameterInstantiation",
+                    "start": 47,
+                    "end": 53,
+                    "loc": {
+                      "start": {
+                        "line": 2,
+                        "column": 29
+                      },
+                      "end": {
+                        "line": 2,
+                        "column": 35
+                      }
+                    },
+                    "params": [
+                      {
+                        "type": "GenericTypeAnnotation",
+                        "start": 48,
+                        "end": 52,
+                        "loc": {
+                          "start": {
+                            "line": 2,
+                            "column": 30
+                          },
+                          "end": {
+                            "line": 2,
+                            "column": 34
+                          }
+                        },
+                        "typeParameters": null,
+                        "id": {
+                          "type": "Identifier",
+                          "start": 48,
+                          "end": 52,
+                          "loc": {
+                            "start": {
+                              "line": 2,
+                              "column": 30
+                            },
+                            "end": {
+                              "line": 2,
+                              "column": 34
+                            },
+                            "identifierName": "File"
+                          },
+                          "name": "File"
+                        }
+                      }
+                    ]
+                  },
+                  "id": {
+                    "type": "Identifier",
+                    "start": 39,
+                    "end": 47,
+                    "loc": {
+                      "start": {
+                        "line": 2,
+                        "column": 21
+                      },
+                      "end": {
+                        "line": 2,
+                        "column": 29
+                      },
+                      "identifierName": "Iterator"
+                    },
+                    "name": "Iterator"
+                  }
+                }
+              },
+              "optional": false
+            }
+          ],
+          "indexers": [],
+          "exact": false
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babylon/test/fixtures/flow/iterator/03/input.js b/packages/babylon/test/fixtures/flow/iterator/03/input.js
new file mode 100644
index 0000000000..16c6bb95da
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/03/input.js
@@ -0,0 +1 @@
+var @@asyncIterator;
diff --git a/packages/babylon/test/fixtures/flow/iterator/03/options.json b/packages/babylon/test/fixtures/flow/iterator/03/options.json
new file mode 100644
index 0000000000..7bad2fe143
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/03/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Invalid identifier @@asyncIterator (1:19)"
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/04/input.js b/packages/babylon/test/fixtures/flow/iterator/04/input.js
new file mode 100644
index 0000000000..cc6faf0462
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/04/input.js
@@ -0,0 +1 @@
+var @@iterator;
diff --git a/packages/babylon/test/fixtures/flow/iterator/04/options.json b/packages/babylon/test/fixtures/flow/iterator/04/options.json
new file mode 100644
index 0000000000..ae3871cf99
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/04/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Invalid identifier @@iterator (1:14)"
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/05/input.js b/packages/babylon/test/fixtures/flow/iterator/05/input.js
new file mode 100644
index 0000000000..5271a1c31f
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/05/input.js
@@ -0,0 +1,3 @@
+class T {
+  @@asyncIterator(){}
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/05/options.json b/packages/babylon/test/fixtures/flow/iterator/05/options.json
new file mode 100644
index 0000000000..9d235ec74a
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/05/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Invalid identifier @@asyncIterator (2:17)"
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/06/input.js b/packages/babylon/test/fixtures/flow/iterator/06/input.js
new file mode 100644
index 0000000000..5732a16269
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/06/input.js
@@ -0,0 +1,3 @@
+class T {
+  @@iterator(){}
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/06/options.json b/packages/babylon/test/fixtures/flow/iterator/06/options.json
new file mode 100644
index 0000000000..515a2cba19
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/06/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Invalid identifier @@iterator (2:12)"
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/07/input.js b/packages/babylon/test/fixtures/flow/iterator/07/input.js
new file mode 100644
index 0000000000..5bb6e3cf73
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/07/input.js
@@ -0,0 +1 @@
+type @@iterator = number
diff --git a/packages/babylon/test/fixtures/flow/iterator/07/options.json b/packages/babylon/test/fixtures/flow/iterator/07/options.json
new file mode 100644
index 0000000000..4c1f323d16
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/07/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Invalid identifier @@iterator (1:15)"
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/08/input.js b/packages/babylon/test/fixtures/flow/iterator/08/input.js
new file mode 100644
index 0000000000..fcc77cf3f8
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/08/input.js
@@ -0,0 +1 @@
+type @@asyncIterator = number
diff --git a/packages/babylon/test/fixtures/flow/iterator/08/options.json b/packages/babylon/test/fixtures/flow/iterator/08/options.json
new file mode 100644
index 0000000000..3efa2ffcd0
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/08/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Invalid identifier @@asyncIterator (1:20)"
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/09/input.js b/packages/babylon/test/fixtures/flow/iterator/09/input.js
new file mode 100644
index 0000000000..2bec164865
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/09/input.js
@@ -0,0 +1,3 @@
+let x = {
+  @@iterator() {}
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/09/options.json b/packages/babylon/test/fixtures/flow/iterator/09/options.json
new file mode 100644
index 0000000000..515a2cba19
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/09/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Invalid identifier @@iterator (2:12)"
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/10/input.js b/packages/babylon/test/fixtures/flow/iterator/10/input.js
new file mode 100644
index 0000000000..b98960ea1d
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/10/input.js
@@ -0,0 +1,3 @@
+let x = {
+  @@asyncIterator() {}
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/10/options.json b/packages/babylon/test/fixtures/flow/iterator/10/options.json
new file mode 100644
index 0000000000..9d235ec74a
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/10/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Invalid identifier @@asyncIterator (2:17)"
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/11/input.js b/packages/babylon/test/fixtures/flow/iterator/11/input.js
new file mode 100644
index 0000000000..bb9066173d
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/11/input.js
@@ -0,0 +1,3 @@
+let x = {
+  @@random() {}
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/11/options.json b/packages/babylon/test/fixtures/flow/iterator/11/options.json
new file mode 100644
index 0000000000..248b8a4d9d
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/11/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Invalid identifier @@random (2:10)"
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/12/input.js b/packages/babylon/test/fixtures/flow/iterator/12/input.js
new file mode 100644
index 0000000000..a97778edc8
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/12/input.js
@@ -0,0 +1,3 @@
+function foo(): { @@iterator: () => string } {
+  return (0: any);
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/12/output.json b/packages/babylon/test/fixtures/flow/iterator/12/output.json
new file mode 100644
index 0000000000..c599c26962
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/12/output.json
@@ -0,0 +1,277 @@
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+  "end": 67,
+  "loc": {
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+    "end": {
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+      "column": 1
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+    "end": 67,
+    "loc": {
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+      "end": {
+        "line": 3,
+        "column": 1
+      }
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+    "sourceType": "module",
+    "body": [
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+        "type": "FunctionDeclaration",
+        "start": 0,
+        "end": 67,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 1
+          }
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+          "end": 12,
+          "loc": {
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+              "column": 9
+            },
+            "end": {
+              "line": 1,
+              "column": 12
+            },
+            "identifierName": "foo"
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+        "async": false,
+        "params": [],
+        "predicate": null,
+        "returnType": {
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+          "end": 44,
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+            },
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+            "exact": false
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+                  "column": 2
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+                  "column": 18
+                }
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+              "argument": {
+                "type": "TypeCastExpression",
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+                "end": 63,
+                "loc": {
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+                    "column": 10
+                  },
+                  "end": {
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+                    "column": 16
+                  }
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+                  "type": "NumericLiteral",
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+                  "end": 58,
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+                    "raw": "0"
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+                  "start": 58,
+                  "end": 63,
+                  "loc": {
+                    "start": {
+                      "line": 2,
+                      "column": 11
+                    },
+                    "end": {
+                      "line": 2,
+                      "column": 16
+                    }
+                  },
+                  "typeAnnotation": {
+                    "type": "AnyTypeAnnotation",
+                    "start": 60,
+                    "end": 63,
+                    "loc": {
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+                      "end": {
+                        "line": 2,
+                        "column": 16
+                      }
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+                  }
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+                "extra": {
+                  "parenthesized": true,
+                  "parenStart": 56
+                }
+              }
+            }
+          ],
+          "directives": []
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babylon/test/fixtures/flow/iterator/13/input.js b/packages/babylon/test/fixtures/flow/iterator/13/input.js
new file mode 100644
index 0000000000..568645dca8
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/13/input.js
@@ -0,0 +1,3 @@
+function foo(): { @@asyncIterator: () => string } {
+  return (0: any);
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/13/output.json b/packages/babylon/test/fixtures/flow/iterator/13/output.json
new file mode 100644
index 0000000000..43ac1dab55
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/13/output.json
@@ -0,0 +1,277 @@
+{
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+  "start": 0,
+  "end": 72,
+  "loc": {
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+      "column": 0
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+      "column": 1
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+      "end": {
+        "line": 3,
+        "column": 1
+      }
+    },
+    "sourceType": "module",
+    "body": [
+      {
+        "type": "FunctionDeclaration",
+        "start": 0,
+        "end": 72,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
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+            "line": 3,
+            "column": 1
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+        },
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+        "async": false,
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+        "predicate": null,
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+          "end": 49,
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+            },
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+              "line": 1,
+              "column": 49
+            }
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+            "end": 49,
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+                  "returnType": {
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+                      "end": {
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+                },
+                "variance": null,
+                "optional": false
+              }
+            ],
+            "indexers": [],
+            "exact": false
+          }
+        },
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+          "type": "BlockStatement",
+          "start": 50,
+          "end": 72,
+          "loc": {
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+              "column": 50
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+}
\ No newline at end of file
diff --git a/packages/babylon/test/fixtures/flow/iterator/14/input.js b/packages/babylon/test/fixtures/flow/iterator/14/input.js
new file mode 100644
index 0000000000..ad7b034dc6
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/14/input.js
@@ -0,0 +1,3 @@
+interface A {
+  @@iterator(): Iterator<File>;
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/14/output.json b/packages/babylon/test/fixtures/flow/iterator/14/output.json
new file mode 100644
index 0000000000..79013398e6
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/14/output.json
@@ -0,0 +1,225 @@
+{
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+  "end": 47,
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+      "column": 0
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+      "column": 1
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+        "column": 1
+      }
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+        "end": 47,
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+            "column": 0
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+            "line": 3,
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+          "end": 11,
+          "loc": {
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+              "column": 10
+            },
+            "end": {
+              "line": 1,
+              "column": 11
+            },
+            "identifierName": "A"
+          },
+          "name": "A"
+        },
+        "typeParameters": null,
+        "extends": [],
+        "mixins": [],
+        "body": {
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+          "end": 47,
+          "loc": {
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+              "column": 12
+            },
+            "end": {
+              "line": 3,
+              "column": 1
+            }
+          },
+          "callProperties": [],
+          "properties": [
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+              "start": 16,
+              "end": 44,
+              "loc": {
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+                  "column": 2
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+                  "column": 30
+                }
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+                "end": 26,
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+                    "line": 2,
+                    "column": 2
+                  },
+                  "end": {
+                    "line": 2,
+                    "column": 12
+                  },
+                  "identifierName": "@@iterator"
+                },
+                "name": "@@iterator"
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+              "kind": "init",
+              "method": true,
+              "value": {
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+                "loc": {
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+                "returnType": {
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+                  "end": 44,
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+                      "line": 2,
+                      "column": 30
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+                  },
+                  "typeParameters": {
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+                    "end": 44,
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+                        "column": 30
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+                        "end": 43,
+                        "loc": {
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+                          "end": 43,
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+                    "end": 38,
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+                        "column": 24
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+                      "identifierName": "Iterator"
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+                  }
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+            }
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+          "exact": false
+        }
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+  }
+}
\ No newline at end of file
diff --git a/packages/babylon/test/fixtures/flow/iterator/15/input.js b/packages/babylon/test/fixtures/flow/iterator/15/input.js
new file mode 100644
index 0000000000..f8c4616be8
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/15/input.js
@@ -0,0 +1,3 @@
+interface A {
+  @@asyncIterator(): Iterator<File>;
+}
diff --git a/packages/babylon/test/fixtures/flow/iterator/15/output.json b/packages/babylon/test/fixtures/flow/iterator/15/output.json
new file mode 100644
index 0000000000..c9a648a19c
--- /dev/null
+++ b/packages/babylon/test/fixtures/flow/iterator/15/output.json
@@ -0,0 +1,225 @@
+{
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+  "end": 52,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
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+      "column": 1
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+    "loc": {
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+        "column": 0
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+      "end": {
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+        "column": 1
+      }
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+        "end": 52,
+        "loc": {
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+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 1
+          }
+        },
+        "id": {
+          "type": "Identifier",
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+          "end": 11,
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