diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavascriptClientCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavascriptClientCodegen.java
index f84bd77a5ed..5556d3e04b6 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavascriptClientCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavascriptClientCodegen.java
@@ -215,7 +215,7 @@ public class JavascriptClientCodegen extends DefaultCodegen implements CodegenCo
         if (additionalProperties.containsKey(USE_ES6)) {
             setUseES6(convertPropertyToBooleanAndWriteBack(USE_ES6));
         } else {
-            setUseES6(false); // default to ES5
+            setUseES6(true); // default to ES6
         }
         super.processOpts();