diff --git a/types/form-model/form.d.ts b/types/form-model/form.d.ts
index 6e13e810c..5c1baf922 100644
--- a/types/form-model/form.d.ts
+++ b/types/form-model/form.d.ts
@@ -153,7 +153,7 @@ export declare class FormModel extends AntdComponent {
    * and an object containing all fields that fail the validation. Returns a promise if callback is omitted
    * @type Function
    */
-  validate: (callback?: (boolean: Boolean, object: Object) => void) => void | Promise<any>;
+  validate: (callback?: (boolean: boolean, object: Object) => void) => void | Promise<any>;
 
   /**
    * validate one or several form items