diff --git a/packages/field/src/field.vue b/packages/field/src/field.vue
index 1a10aafbf..011fdae8a 100644
--- a/packages/field/src/field.vue
+++ b/packages/field/src/field.vue
@@ -95,6 +95,14 @@ export default {
     };
   },
 
+  mounted() {
+    if (this.autosize && this.type === 'textarea') {
+      const el = this.$refs.textareaElement;
+      el.style.height = el.scrollHeight + 'px';
+      el.style.overflowY = 'hidden';
+    }
+  },
+
   watch: {
     value(val) {
       this.currentValue = val;
@@ -102,7 +110,7 @@ export default {
 
     currentValue(val) {
       if (this.autosize && this.type === 'textarea') {
-        this.$nextTick(() => this.sizeAdjust());
+        this.$nextTick(this.sizeAdjust);
       }
       this.$emit('input', val);
     }
@@ -125,12 +133,9 @@ export default {
     },
 
     sizeAdjust() {
-      const textareaElement = this.$refs.textareaElement;
-      const textAreaDiff = (parseInt(textareaElement.style.paddingBottom, 10) +
-          parseInt(textareaElement.style.paddingTop, 10)) || 0;
-      // 需要先设为0， 才可以让scrollHeight正确计算。
-      textareaElement.style.height = 0 + 'px';
-      textareaElement.style.height = (textareaElement.scrollHeight - textAreaDiff) + 'px';
+      const el = this.$refs.textareaElement;
+      el.style.height = 'auto';
+      el.style.height = el.scrollHeight + 'px';
     },
 
     handleInputFocus() {
diff --git a/packages/mixins/popup/index.js b/packages/mixins/popup/index.js
index 95af13559..44700d419 100644
--- a/packages/mixins/popup/index.js
+++ b/packages/mixins/popup/index.js
@@ -4,16 +4,12 @@ import PopupContext from './popup-context';
 
 export default {
   props: {
-    /**
-     * popup当前显示状态
-     */
+    // popup当前显示状态
     value: {
       type: Boolean,
       default: false
     },
-    /**
-     * 是否显示遮罩层
-     */
+    // 是否显示遮罩层
     overlay: {
       type: Boolean,
       default: false
@@ -26,13 +22,16 @@ export default {
       default: false
     },
     zIndex: [String, Number],
-    /**
-     * popup滚动时是否body内容也滚动
-     * 默认为不滚动
-     */
+    // popup滚动时是否body内容也滚动
+    // 默认为不滚动
     lockOnScroll: {
       type: Boolean,
       default: true
+    },
+    // 防止滚动穿透
+    preventScroll: {
+      type: Boolean,
+      default: false
     }
   },
 
@@ -137,8 +136,11 @@ export default {
       this.$el.style.zIndex = PopupManager.nextZIndex();
       this.opened = true;
       this.opening = false;
-      document.addEventListener('touchstart', this.recordPosition, false);
-      document.addEventListener('touchmove', this.watchTouchMove, false);
+
+      if (this.preventScroll) {
+        document.addEventListener('touchstart', this.recordPosition, false);
+        document.addEventListener('touchmove', this.watchTouchMove, false);        
+      }
     },
 
     /**
@@ -167,8 +169,11 @@ export default {
     doAfterClose() {
       this.closing = false;
       PopupManager.closeModal(this._popupId);
-      document.removeEventListener('touchstart', this.recordPosition, false);
-      document.removeEventListener('touchmove', this.watchTouchMove, false);
+
+      if (this.preventScroll) {
+        document.removeEventListener('touchstart', this.recordPosition, false);
+        document.removeEventListener('touchmove', this.watchTouchMove, false);
+      }
     }
   },