diff --git a/src/components/editor/keymap.ts b/src/components/editor/keymap.ts
index 74da91e..7c696e0 100644
--- a/src/components/editor/keymap.ts
+++ b/src/components/editor/keymap.ts
@@ -28,6 +28,7 @@ export const extraKeymap = {
   "Mod-y": redo,
   "Mod-b": toggleMark(schema.marks.bold),
   "Mod-i": toggleMark(schema.marks.italic),
+  "Mod-u": toggleMark(schema.marks.underline),
   "Mod-`": toggleMark(schema.marks.code),
   "Mod-1": setBlockType(schema.nodes.heading, { level: 1 }),
   "Mod-2": setBlockType(schema.nodes.heading, { level: 2 }),
diff --git a/src/components/editor/schema.ts b/src/components/editor/schema.ts
index 65feece..7d13d45 100644
--- a/src/components/editor/schema.ts
+++ b/src/components/editor/schema.ts
@@ -104,6 +104,12 @@ export const schema = new Schema({
         return ["i", 0];
       },
     },
+    underline: {
+      parseDOM: [{ tag: "u" }],
+      toDOM() {
+        return ["u", 0];
+      },
+    },
     del: {
       parseDOM: [{ tag: "del" }],
       toDOM() {
diff --git a/src/styles/Icons.css b/src/styles/Icons.css
index e80c877..7a06cf5 100644
--- a/src/styles/Icons.css
+++ b/src/styles/Icons.css
@@ -46,6 +46,10 @@
   content: "\e23f";
 }
 
+.i-underline::before {
+  content: "\e249";
+}
+
 .i-strikethrough::before {
   content: "\e257";
 }
diff --git a/src/views/NoteView.vue b/src/views/NoteView.vue
index 78e1f10..5964e66 100644
--- a/src/views/NoteView.vue
+++ b/src/views/NoteView.vue
@@ -151,6 +151,12 @@ const editorTools = [
     active: () => editor.value!.isMarkActive("italic"),
     enable: () => true,
   },
+  {
+    icon: "i i-m i-underline",
+    command: () => editor.value!.toggleMark("underline"),
+    active: () => editor.value!.isMarkActive("underline"),
+    enable: () => true,
+  },
   {
     icon: "i i-m i-strikethrough",
     command: () => editor.value!.toggleMark("del"),