diff --git a/packages/slider/README.md b/packages/slider/README.md
index 23a22e04..03e02d8b 100644
--- a/packages/slider/README.md
+++ b/packages/slider/README.md
@@ -91,7 +91,7 @@ Page({
 | max | 最大值 | *number* | `100` |
 | min | 最小值 | *number* | `0` |
 | step | 步长 | *number* | `1` |
-| bar-height | 进度条高度 | *string* | `2px` |
+| bar-height | 进度条高度，默认单位为 `px` | *string \| number* | `2px` |
 | active-color | 进度条激活态颜色 | *string* | `#1989fa` |
 | inactive-color | 进度条默认颜色 | *string* | `#e5e5e5` |
 
diff --git a/packages/slider/index.ts b/packages/slider/index.ts
index 782103d5..53138e56 100644
--- a/packages/slider/index.ts
+++ b/packages/slider/index.ts
@@ -1,6 +1,7 @@
 import { VantComponent } from '../common/component';
 import { touch } from '../mixins/touch';
 import { Weapp } from 'definitions/weapp';
+import { addUnit } from '../common/utils';
 
 VantComponent({
   mixins: [touch],
@@ -27,7 +28,7 @@ VantComponent({
       value: 0
     },
     barHeight: {
-      type: String,
+      type: null,
       value: '2px'
     }
   },
@@ -77,10 +78,11 @@ VantComponent({
 
     updateValue(value: number, end: boolean, drag: boolean) {
       value = this.format(value);
+      const { barHeight } = this.data;
 
       this.set({
         value,
-        barStyle: `width: ${value}%; height: ${this.data.barHeight};`
+        barStyle: `width: ${value}%; height: ${addUnit(barHeight)};`
       });
 
       if (drag) {