diff --git a/types/yup/index.d.ts b/types/yup/index.d.ts
index e6dc35c1ea..c8c3f2dda4 100644
--- a/types/yup/index.d.ts
+++ b/types/yup/index.d.ts
@@ -46,6 +46,7 @@ export interface Schema<T> {
     default(value?: any): this;
     nullable(isNullable: boolean): this;
     required(message?: string): this;
+    notRequired(): this;
     typeError(message?: string): this;
     oneOf(arrayOfValues: any[], message?: string): this;
     notOneOf(arrayOfValues: any[], message?: string): this;
diff --git a/types/yup/yup-tests.ts b/types/yup/yup-tests.ts
index 9dd02ced73..0c0aa04c47 100644
--- a/types/yup/yup-tests.ts
+++ b/types/yup/yup-tests.ts
@@ -100,6 +100,7 @@ mixed.default(() => ({ number: 5}));
 mixed.default();
 mixed.nullable(true);
 mixed.required();
+mixed.notRequired(); // $ExpectType MixedSchema
 mixed.typeError('type error');
 mixed.oneOf(['hello', 'world'], 'message');
 mixed.notOneOf(['hello', 'world'], 'message');