diff --git a/packages/babel-generator/README.md b/packages/babel-generator/README.md
index 46a4c051b3..e3882c9af2 100644
--- a/packages/babel-generator/README.md
+++ b/packages/babel-generator/README.md
@@ -37,7 +37,6 @@ minified               | boolean  | `false`         | Should the output be minif
 concise                | boolean  | `false`         | Set to `true` to reduce whitespace (but not as much as `opts.compact`)
 quotes                 | `'single'` or `'double'` | autodetect based on `ast.tokens` | The type of quote to use in the output
 filename               | string   |                 | Used in warning messages
-flowCommaSeparator     | boolean  | `false`         | Set to `true` to use commas instead of semicolons as Flow property separators
 jsonCompatibleStrings  | boolean  | `false`         | Set to true to run `jsesc` with "json": true to print "\u00A9" vs. "©";
 Options for source maps:
 
diff --git a/packages/babel-generator/src/generators/flow.js b/packages/babel-generator/src/generators/flow.js
index 668ba0e2b3..2e96843eaf 100644
--- a/packages/babel-generator/src/generators/flow.js
+++ b/packages/babel-generator/src/generators/flow.js
@@ -277,11 +277,7 @@ export function ObjectTypeAnnotation(node: Object) {
       statement: true,
       iterator: () => {
         if (props.length !== 1) {
-          if (this.format.flowCommaSeparator) {
-            this.token(",");
-          } else {
-            this.semicolon();
-          }
+          this.token(",");
           this.space();
         }
       }
diff --git a/packages/babel-generator/src/index.js b/packages/babel-generator/src/index.js
index 138336546c..fce0c97a03 100644
--- a/packages/babel-generator/src/index.js
+++ b/packages/babel-generator/src/index.js
@@ -64,8 +64,7 @@ function normalizeOptions(code, opts, tokens): Format {
       adjustMultilineComment: true,
       style: style,
       base: 0
-    },
-    flowCommaSeparator: opts.flowCommaSeparator,
+    }
   };
 
   if (format.minified) {
diff --git a/packages/babel-generator/test/fixtures/flow/call-properties/expected.js b/packages/babel-generator/test/fixtures/flow/call-properties/expected.js
index 11d4f2a107..f0b5dabbe3 100644
--- a/packages/babel-generator/test/fixtures/flow/call-properties/expected.js
+++ b/packages/babel-generator/test/fixtures/flow/call-properties/expected.js
@@ -1,5 +1,5 @@
 var a: { (): number };
 var a: { (): number };
-var a: { y: string; (): number; (x: string): string; };
+var a: { y: string, (): number, (x: string): string, };
 var a: { <T>(x: T): number };
 interface A { (): number };
diff --git a/packages/babel-generator/test/fixtures/flow/declare-statements/expected.js b/packages/babel-generator/test/fixtures/flow/declare-statements/expected.js
index 8f667c0137..7498e25025 100644
--- a/packages/babel-generator/test/fixtures/flow/declare-statements/expected.js
+++ b/packages/babel-generator/test/fixtures/flow/declare-statements/expected.js
@@ -6,7 +6,7 @@ declare function foo<T>(): void;
 declare function foo(x: number, y: string): void;
 declare class A {}
 declare class A<T> extends B<T> { x: number }
-declare class A { static foo: () => number; static x: string; }
+declare class A { static foo: () => number, static x: string, }
 declare class A { static [indexer: number]: string }
 declare class A { static (): number }
 declare class A mixins B<T>, C {}
diff --git a/packages/babel-generator/test/fixtures/flow/interfaces-module-and-script/expected.js b/packages/babel-generator/test/fixtures/flow/interfaces-module-and-script/expected.js
index ee084a80b7..89aa627760 100644
--- a/packages/babel-generator/test/fixtures/flow/interfaces-module-and-script/expected.js
+++ b/packages/babel-generator/test/fixtures/flow/interfaces-module-and-script/expected.js
@@ -2,7 +2,7 @@ interface A {};
 interface A extends B {};
 interface A<T> extends B<T>, C<T> {};
 interface A { foo: () => number };
-interface Dictionary { length: number; [index: string]: string; };
+interface Dictionary { length: number, [index: string]: string, };
 class Foo implements Bar {}
 class Foo extends Bar implements Bat, Man<number> {}
 class Foo extends class Bar implements Bat {} {}
diff --git a/packages/babel-generator/test/fixtures/flow/type-annotations/expected.js b/packages/babel-generator/test/fixtures/flow/type-annotations/expected.js
index 205513cb00..e90a7bcfc4 100644
--- a/packages/babel-generator/test/fixtures/flow/type-annotations/expected.js
+++ b/packages/babel-generator/test/fixtures/flow/type-annotations/expected.js
@@ -38,14 +38,14 @@ var numVal: number;
 var numVal: number = otherNumVal;
 var a: { numVal: number };
 var a: { numVal: number };
-var a: { numVal: number; [indexer: string]: number; };
+var a: { numVal: number, [indexer: string]: number, };
 var a: ?{ numVal: number };
-var a: { numVal: number; strVal: string; };
+var a: { numVal: number, strVal: string, };
 var a: { subObj: { strVal: string } };
 var a: { subObj: ?{ strVal: string } };
-var a: { param1: number; param2: string; };
-var a: { param1: number; param2?: string; };
-var a: { [a: number]: string; [b: number]: string; };
+var a: { param1: number, param2: string, };
+var a: { param1: number, param2?: string, };
+var a: { [a: number]: string, [b: number]: string, };
 var a: { add: (x: number, ...y: Array<string>) => void };
 var a: { subtract: (x: number, ...y: Array<string>) => void };
 var a: { id: <T>(x: T) => T };
@@ -112,14 +112,14 @@ export interface qux<T> { p: T };
 var a: ?Array<?string>;
 var a: {| numVal: number |};
 var a: {| numVal: number |};
-var a: {| numVal: number; [indexer: string]: number; |};
+var a: {| numVal: number, [indexer: string]: number, |};
 var a: ?{| numVal: number |};
-var a: {| numVal: number; strVal: string; |};
+var a: {| numVal: number, strVal: string, |};
 var a: {| subObj: { strVal: string } |};
 var a: {| subObj: ?{ strVal: string } |};
-var a: {| param1: number; param2: string; |};
-var a: {| param1: number; param2?: string; |};
-var a: {| [a: number]: string; [b: number]: string; |};
+var a: {| param1: number, param2: string, |};
+var a: {| param1: number, param2?: string, |};
+var a: {| [a: number]: string, [b: number]: string, |};
 var a: {| add: (x: number, ...y: Array<string>) => void |};
 var a: {| subtract: (x: number, ...y: Array<string>) => void |};
 var a: {| id: <T>(x: T) => T |};
diff --git a/packages/babel-generator/test/fixtures/flow/typecasts/expected.js b/packages/babel-generator/test/fixtures/flow/typecasts/expected.js
index 69c9dc4b93..61771958e6 100644
--- a/packages/babel-generator/test/fixtures/flow/typecasts/expected.js
+++ b/packages/babel-generator/test/fixtures/flow/typecasts/expected.js
@@ -1,4 +1,4 @@
 (xxx: number);
-({ xxx: 0, yyy: "hey" }: { xxx: number; yyy: string; });
+({ xxx: 0, yyy: "hey" }: { xxx: number, yyy: string, });
 (xxx => xxx + 1: (xxx: number) => number);
 (xxx: number), (yyy: string);
diff --git a/packages/babel-generator/test/fixtures/flowUsesCommas/options.json b/packages/babel-generator/test/fixtures/flowUsesCommas/options.json
deleted file mode 100644
index f50690ec13..0000000000
--- a/packages/babel-generator/test/fixtures/flowUsesCommas/options.json
+++ /dev/null
@@ -1,3 +0,0 @@
-{
-  "flowCommaSeparator": true
-}
diff --git a/packages/babel-generator/test/index.js b/packages/babel-generator/test/index.js
index 813bd57f59..6abefd9ccd 100644
--- a/packages/babel-generator/test/index.js
+++ b/packages/babel-generator/test/index.js
@@ -259,7 +259,7 @@ describe("programmatic generation", function() {
     const output = generate(objectStatement).code;
     assert.equal(output, [
       "{",
-      "  bar: string;",
+      "  bar: string,",
       "}",
     ].join("\n"));
   });
@@ -280,7 +280,7 @@ describe("programmatic generation", function() {
 
     assert.equal(output, [
       "{",
-      "  [key: any]: Test;",
+      "  [key: any]: Test,",
       "}",
     ].join("\n"));
   });
diff --git a/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/actual.js b/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/actual.js
index 1c62d8ee90..7c28264794 100644
--- a/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/actual.js
+++ b/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/actual.js
@@ -6,7 +6,7 @@ declare function foo<T>(): void;
 declare function foo(x: number, y: string): void;
 declare class A {}
 declare class A<T> extends B<T> { x: number }
-declare class A { static foo(): number; static x : string }
+declare class A { static foo(): number, static x : string }
 declare class A { static [ indexer: number]: string }
 declare class A { static () : number }
 declare class A mixins B<T>, C {}
diff --git a/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/expected.js b/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/expected.js
index 1e0c0a5b06..95116a0720 100644
--- a/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/expected.js
+++ b/packages/babel-plugin-transform-flow-comments/test/fixtures/flow-comments/declare-statements/expected.js
@@ -6,7 +6,7 @@
 /*:: declare function foo(x: number, y: string): void;*/
 /*:: declare class A {}*/
 /*:: declare class A<T> extends B<T> { x: number }*/
-/*:: declare class A { static foo(): number; static x : string }*/
+/*:: declare class A { static foo(): number, static x : string }*/
 /*:: declare class A { static [ indexer: number]: string }*/
 /*:: declare class A { static () : number }*/
 /*:: declare class A mixins B<T>, C {}*/