diff --git a/types/options.d.ts b/types/options.d.ts
index a54993fff5d..75ce2257966 100644
--- a/types/options.d.ts
+++ b/types/options.d.ts
@@ -110,7 +110,7 @@ export interface FunctionalComponentOptions<Props = DefaultProps, PropDefs = Pro
   props?: PropDefs;
   inject?: InjectOptions;
   functional: boolean;
-  render(this: undefined, createElement: CreateElement, context: RenderContext<Props>): VNode;
+  render?(this: undefined, createElement: CreateElement, context: RenderContext<Props>): VNode;
 }
 
 export interface RenderContext<Props=DefaultProps> {
diff --git a/types/test/options-test.ts b/types/test/options-test.ts
index a14560fe1b3..45c3d088fe8 100644
--- a/types/test/options-test.ts
+++ b/types/test/options-test.ts
@@ -330,6 +330,10 @@ Vue.component('functional-component-object-inject', {
   }
 })
 
+Vue.component('functional-component-check-optional', {
+  functional: true
+})
+
 Vue.component("async-component", ((resolve, reject) => {
   setTimeout(() => {
     resolve(Vue.component("component"));