diff --git a/components/input-number/index.tsx b/components/input-number/index.tsx
index 9d27c51e4..b86dee422 100644
--- a/components/input-number/index.tsx
+++ b/components/input-number/index.tsx
@@ -12,7 +12,7 @@ export interface InputNumberProps {
   onChange?: (value: number | string | undefined) => void;
   disabled?: boolean;
   size?: 'large' | 'small' | 'default';
-  formatter?: void | ((value: number | string | undefined) => string);
+  formatter?: (value: number | string | undefined) => string;
   placeholder?: string;
   style?: React.CSSProperties;
   className?: string;