diff --git a/lib/6to5/transformation/transformers/playground-memoization-operator.js b/lib/6to5/transformation/transformers/playground-memoization-operator.js
index d8aad48236..1f5fa4bb9f 100644
--- a/lib/6to5/transformation/transformers/playground-memoization-operator.js
+++ b/lib/6to5/transformation/transformers/playground-memoization-operator.js
@@ -6,9 +6,11 @@ var isMemo = function (node) {
   return is;
 };
 
-var getPropRef = function (nodes, prop, file, scope) {
-  if (t.isIdentifier(prop)) {
-    return t.literal(prop.name);
+var getPropRef = function (nodes, member, file, scope) {
+  var prop = member.property;
+  var key = t.toComputedKey(member, member.property);
+  if (t.isLiteral(key)) {
+    return key;
   } else {
     var temp = scope.generateUidBasedOnNode(prop, file);
     nodes.push(t.variableDeclaration("var", [
@@ -54,7 +56,7 @@ exports.ExpressionStatement = function (node, parent, file, scope) {
 
   var left = expr.left;
   var obj  = getObjRef(nodes, left.object, file, scope);
-  var prop = getPropRef(nodes, left.property, file, scope);
+  var prop = getPropRef(nodes, left, file, scope);
 
   nodes.push(t.ifStatement(
     buildHasOwn(obj, prop, file),
@@ -72,7 +74,7 @@ exports.AssignmentExpression = function (node, parent, file, scope) {
 
   var left = node.left;
   var obj  = getObjRef(nodes, left.object, file, scope);
-  var prop = getPropRef(nodes, left.property, file, scope);
+  var prop = getPropRef(nodes, left, file, scope);
 
   nodes.push(t.logicalExpression(
     "&&",