diff --git a/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/JavascriptClientCodegen.java b/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/JavascriptClientCodegen.java
index e7d3f456048..fb2dd0243af 100644
--- a/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/JavascriptClientCodegen.java
+++ b/modules/swagger-codegen/src/main/java/io/swagger/codegen/languages/JavascriptClientCodegen.java
@@ -873,7 +873,7 @@ public CodegenOperation fromOperation(String path, String httpMethod, Operation
     public CodegenModel fromModel(String name, Model model, Map<String, Model> allDefinitions) {
         CodegenModel codegenModel = super.fromModel(name, model, allDefinitions);
 
-        if (allDefinitions != null && codegenModel != null && codegenModel.parent != null && codegenModel.hasEnums) {
+        if (allDefinitions != null && codegenModel != null && codegenModel.parent != null && codegenModel.hasEnums && codegenModel.parentSchema != null) {
             final Model parentModel = allDefinitions.get(codegenModel.parentSchema);
             final CodegenModel parentCodegenModel = super.fromModel(codegenModel.parent, parentModel, allDefinitions);
             codegenModel = JavascriptClientCodegen.reconcileInlineEnums(codegenModel, parentCodegenModel);
@@ -900,6 +900,14 @@ public CodegenModel fromModel(String name, Model model, Map<String, Model> allDe
         return codegenModel;
     }
 
+    @Override
+    protected void addAdditionPropertiesToCodeGenModel(CodegenModel codegenModel, ModelImpl swaggerModel) {
+        super.addAdditionPropertiesToCodeGenModel(codegenModel, swaggerModel);
+        if (swaggerModel.getAdditionalProperties() != null) {
+            codegenModel.additionalPropertiesType = getSwaggerType(swaggerModel.getAdditionalProperties());
+        }
+    }
+
     private String sanitizePath(String p) {
         //prefer replace a ', instead of a fuLL URL encode for readability
         return p.replaceAll("'", "%27");
diff --git a/modules/swagger-codegen/src/main/resources/Javascript/partial_model_generic.mustache b/modules/swagger-codegen/src/main/resources/Javascript/partial_model_generic.mustache
index 11385bd3cbf..97e007fe22c 100644
--- a/modules/swagger-codegen/src/main/resources/Javascript/partial_model_generic.mustache
+++ b/modules/swagger-codegen/src/main/resources/Javascript/partial_model_generic.mustache
@@ -95,6 +95,10 @@
   exports.prototype.{{name}} = {{#defaultValue}}{{{defaultValue}}}{{/defaultValue}}{{^defaultValue}}undefined{{/defaultValue}};
 
 {{/vars}}
+{{#additionalPropertiesType}}
+  exports.prototype.additionalProperties = new Map();
+{{/additionalPropertiesType}}
+
 {{#useInheritance}}
   {{#interfaceModels}}
   // Implement {{classname}} interface: