diff --git a/packages/babel-preset-env/src/utils.js b/packages/babel-preset-env/src/utils.js
index dc81f30e4b00..4184eb745f21 100644
--- a/packages/babel-preset-env/src/utils.js
+++ b/packages/babel-preset-env/src/utils.js
@@ -57,11 +57,11 @@ export function isPolyfillSource(source: ?string): boolean {
 }
 
 const modulePathMap = {
-  "regenerator-runtime": "regenerator-runtime/runtime",
+  "regenerator-runtime": "regenerator-runtime/runtime.js",
 };
 
 export function getModulePath(mod: string): string {
-  return modulePathMap[mod] || `core-js/modules/${mod}`;
+  return modulePathMap[mod] || `core-js/modules/${mod}.js`;
 }
 
 export function createImport(path: NodePath, mod: string) {