diff --git a/api/@internal/component/ets/slider.d.ts b/api/@internal/component/ets/slider.d.ts
index fbbca1732e8ea0aafb7f454b98f9560c329de3fc..3bcfb199915b691191e866dfb34509c66ab0863d 100644
--- a/api/@internal/component/ets/slider.d.ts
+++ b/api/@internal/component/ets/slider.d.ts
@@ -177,6 +177,13 @@ declare class SliderAttribute extends CommonMethod<SliderAttribute> {
    */
   showTips(value: boolean): SliderAttribute;
 
+  /**
+   * Called when the thickness of track is set.
+   * @devices phone, tablet, car
+   * @since 8
+   */
+  trackThickness(value: Length): SliderAttribute;
+
   /**
    * Called when the selection value changes.
    * @devices phone, tablet, car