diff --git a/src/BaseSelect.tsx b/src/BaseSelect.tsx
index 23f4b2c81..f6ccf2e1a 100644
--- a/src/BaseSelect.tsx
+++ b/src/BaseSelect.tsx
@@ -1,5 +1,6 @@
 import * as React from 'react';
 import classNames from 'classnames';
+import type { AlignType } from 'rc-trigger/lib/interface';
 import KeyCode from 'rc-util/lib/KeyCode';
 import isMobile from 'rc-util/lib/isMobile';
 import { useComposeRef } from 'rc-util/lib/ref';
@@ -177,7 +178,7 @@ export interface BaseSelectProps extends BaseSelectPrivateProps, React.AriaAttri
   dropdownClassName?: string;
   dropdownMatchSelectWidth?: boolean | number;
   dropdownRender?: (menu: React.ReactElement) => React.ReactElement;
-  dropdownAlign?: any;
+  dropdownAlign?: AlignType;
   placement?: Placement;
   getPopupContainer?: RenderDOMFunc;
 
diff --git a/src/SelectTrigger.tsx b/src/SelectTrigger.tsx
index 00d051b72..530be5ec0 100644
--- a/src/SelectTrigger.tsx
+++ b/src/SelectTrigger.tsx
@@ -1,5 +1,6 @@
 import * as React from 'react';
 import Trigger from 'rc-trigger';
+import type { AlignType } from 'rc-trigger/lib/interface';
 import classNames from 'classnames';
 import type { Placement, RenderDOMFunc } from './BaseSelect';
 
@@ -63,7 +64,7 @@ export interface SelectTriggerProps {
   dropdownMatchSelectWidth?: boolean | number;
   dropdownRender?: (menu: React.ReactElement) => React.ReactElement;
   getPopupContainer?: RenderDOMFunc;
-  dropdownAlign: object;
+  dropdownAlign: AlignType;
   empty: boolean;
 
   getTriggerDOMNode: () => HTMLElement;