diff --git a/engine/cocos2d/core/renderer/utils/label/bmfont.js b/engine/cocos2d/core/renderer/utils/label/bmfont.js
index ccce272b..c4e8b4cf 100644
--- a/engine/cocos2d/core/renderer/utils/label/bmfont.js
+++ b/engine/cocos2d/core/renderer/utils/label/bmfont.js
@@ -232,6 +232,10 @@ export default class BmfontAssembler extends Assembler2D {
         }
     }
 
+    _clearHorizontalKerning() {
+        _horizontalKernings.length = 0;
+    }
+
     _multilineTextWrap (nextTokenFunc) {
         let textLen = _string.length;
 
diff --git a/engine/cocos2d/core/renderer/utils/label/letter-font.js b/engine/cocos2d/core/renderer/utils/label/letter-font.js
index b90534e3..9b815ce7 100644
--- a/engine/cocos2d/core/renderer/utils/label/letter-font.js
+++ b/engine/cocos2d/core/renderer/utils/label/letter-font.js
@@ -560,7 +560,11 @@ export default class LetterFontAssembler extends WebglBmfontAssembler {
 
         return fontDesc;
     }
-    _computeHorizontalKerningForText () {}
+
+    _computeHorizontalKerningForText () {
+        this._clearHorizontalKerning();
+    }
+
     _determineRect (tempRect) {
         return false;
     }