diff --git a/src/controllers/constant.js b/src/controllers/constant.js
index 4c17884..af2a2c8 100644
--- a/src/controllers/constant.js
+++ b/src/controllers/constant.js
@@ -943,6 +943,20 @@ function menuToolBar (){
                 </div>
             </div>
         </div>
+        <div class="luckysheet-toolbar-button luckysheet-inline-block" data-tips="${toolbar.underline}"
+        id="luckysheet-icon-underline" role="button" style="user-select: none;">
+            <div class="luckysheet-toolbar-button-outer-box luckysheet-inline-block"
+            style="user-select: none;">
+                <div class="luckysheet-toolbar-button-inner-box luckysheet-inline-block"
+                style="user-select: none;">
+                    <div class="luckysheet-icon luckysheet-inline-block " style="user-select: none;">
+                        <div aria-hidden="true" class="luckysheet-icon-img-container luckysheet-icon-img luckysheet-icon-underline iconfont icon-wenbenxiahuaxian"
+                        style="user-select: none;">
+                        </div>
+                    </div>
+                </div>
+            </div>
+        </div>
         <div class="luckysheet-toolbar-button-split-left luckysheet-toolbar-button luckysheet-inline-block luckysheet-icon-text-color"
         data-tips="${toolbar.textColor}" id="luckysheet-icon-text-color" role="button" style="user-select: none;">
             <div class="luckysheet-toolbar-button-outer-box luckysheet-inline-block"
diff --git a/src/controllers/keyboard.js b/src/controllers/keyboard.js
index 4cc4d09..c1e7d57 100644
--- a/src/controllers/keyboard.js
+++ b/src/controllers/keyboard.js
@@ -746,6 +746,10 @@ export function keyboardInitial(){
                     //Alt + Shift + 5（删除线）
                     $("#luckysheet-icon-strikethrough").click();
                 }
+                // else if (altKey && (kcode == 54 || kcode == 102)) {
+                //     //Alt + Shift + 6（删除线）
+                //     $("#luckysheet-icon-underline").click();
+                // }
 
                 event.preventDefault();
             }
diff --git a/src/controllers/menuButton.js b/src/controllers/menuButton.js
index 98df616..5d4d070 100644
--- a/src/controllers/menuButton.js
+++ b/src/controllers/menuButton.js
@@ -2225,6 +2225,27 @@ const menuButton = {
             _this.menuButtonFocus(d, row_index, col_index);
         });
 
+        //下划线
+        $("#luckysheet-icon-underline").mousedown(function(e){
+            hideMenuByCancel(e);
+            e.stopPropagation();
+        }).click(function(){
+            let d = editor.deepCopyFlowData(Store.flowdata);
+            let row_index = Store.luckysheet_select_save[0]["row_focus"], 
+                col_index = Store.luckysheet_select_save[0]["column_focus"];
+            let foucsStatus = _this.checkstatus(d, row_index, col_index, "un");
+
+            if(foucsStatus == 1){
+                foucsStatus = 0;
+            }
+            else{
+                foucsStatus = 1;
+            }
+
+            _this.updateFormat(d, "un", foucsStatus);
+            _this.menuButtonFocus(d, row_index, col_index);
+        });
+
         //条件格式
         $("#luckysheet-icon-conditionformat").click(function(){
             let menuButtonId = $(this).attr("id") + "-menuButton";
@@ -3372,7 +3393,6 @@ const menuButton = {
         if(_locale==null){
             _locale = locale();
         }
-        
         const locale_fontarray = _locale.fontarray;
         const locale_fontjson = _locale.fontjson;
 
@@ -3400,6 +3420,14 @@ const menuButton = {
                 $("#luckysheet-icon-strikethrough").removeClass("luckysheet-toolbar-button-hover");
             }
         }
+        else if(attr == "un"){
+            if(foucsStatus != "0"){
+                $("#luckysheet-icon-underline").addClass("luckysheet-toolbar-button-hover");
+            }
+            else{
+                $("#luckysheet-icon-underline").removeClass("luckysheet-toolbar-button-hover");
+            }
+        }
         else if(attr == "ff"){
             let menuButtonId = "luckysheet-icon-font-family-menuButton";
             let $menuButton = $("#" + menuButtonId);
@@ -3560,7 +3588,7 @@ const menuButton = {
     },
     menuButtonFocus: function(d, r, c){
         let _this = this;
-        let foucsList = ["bl", "it", "cl", "ff", "ht", "vt", "fs", "tb", "tr", "ct"];
+        let foucsList = ["bl", "it", "cl", "ff", "ht", "vt", "fs", "tb", "tr", "ct", "un"];
         const _locale = locale();
         for(let i = 0; i < foucsList.length; i++){
             let attr = foucsList[i];
diff --git a/src/controllers/resize.js b/src/controllers/resize.js
index 5ca3935..5aa3f02 100644
--- a/src/controllers/resize.js
+++ b/src/controllers/resize.js
@@ -309,6 +309,7 @@ export function menuToolBarWidth() {
         $('#luckysheet-icon-bold').offset().left,
         $('#luckysheet-icon-italic').offset().left,
         $('#luckysheet-icon-strikethrough').offset().left,
+        $('#luckysheet-icon-underline').offset().left,
         $('#luckysheet-icon-text-color').offset().left,
         $('#luckysheet-icon-cell-color').offset().left,
         $('#luckysheet-icon-border-all').offset().left,
@@ -347,6 +348,7 @@ export function menuToolBarWidth() {
         '#luckysheet-icon-bold',
         '#luckysheet-icon-italic',
         '#luckysheet-icon-strikethrough',
+        '#luckysheet-icon-underline',
         ['#luckysheet-icon-text-color','#luckysheet-icon-text-color-menu','#toolbar-separator-text-color'],
         ['#luckysheet-icon-cell-color','#luckysheet-icon-cell-color-menu'],
         ['#luckysheet-icon-border-all','#luckysheet-icon-border-menu'],
diff --git a/src/locale/en.js b/src/locale/en.js
index 05a87fd..1ad818d 100644
--- a/src/locale/en.js
+++ b/src/locale/en.js
@@ -8826,6 +8826,7 @@ export default {
         bold: 'Bold (Ctrl+B)',
         italic : 'Italic (Ctrl+I)',
         strikethrough: 'Strikethrough (Alt+Shift+5)',
+        underline: 'Underline',
         textColor: 'Text color',
         chooseColor: 'choose color',
         resetColor: 'Reset',
diff --git a/src/locale/es.js b/src/locale/es.js
index b455ca2..14138fb 100644
--- a/src/locale/es.js
+++ b/src/locale/es.js
@@ -8826,6 +8826,7 @@ export default {
         bold: 'Negrita (Ctrl+B)',
         italic : 'Itálica (Ctrl+I)',
         strikethrough: 'Tachar (Alt+Shift+5)',
+        underline: 'Guion bajo',
         textColor: 'Color texto',
         chooseColor: 'elegir color',
         resetColor: 'Reinicializar',
diff --git a/src/locale/zh.js b/src/locale/zh.js
index 6818780..23af7e0 100644
--- a/src/locale/zh.js
+++ b/src/locale/zh.js
@@ -9052,6 +9052,7 @@ export default {
         bold: '粗体 (Ctrl+B)',
         italic: '斜体 (Ctrl+I)',
         strikethrough: '删除线 (Alt+Shift+5)',
+        underline: '下划线',
         textColor: '文本颜色',
         chooseColor: '颜色选择',
         resetColor: '重置颜色',