diff --git a/src/browser/index.jsx b/src/browser/index.jsx
index 60653f18..481ccdd7 100644
--- a/src/browser/index.jsx
+++ b/src/browser/index.jsx
@@ -25,7 +25,8 @@ var MainPage = React.createClass({
       key: 0,
       unreadCounts: new Array(this.props.teams.length),
       mentionCounts: new Array(this.props.teams.length),
-      unreadAtActive: new Array(this.props.teams.length)
+      unreadAtActive: new Array(this.props.teams.length),
+      mentionAtActive: new Array(this.props.teams.length)
     };
   },
   componentDidMount: function() {
@@ -60,11 +61,14 @@ var MainPage = React.createClass({
     });
     this.handleUnreadCountTotalChange();
   },
-  handleUnreadAtActiveChange: function(index, state) {
+  handleUnreadAtActiveChange: function(index, isUnread, isMentioned) {
     var unreadAtActive = this.state.unreadAtActive;
-    unreadAtActive[index] = state;
+    var mentionAtActive = this.state.mentionAtActive;
+    unreadAtActive[index] = isUnread;
+    mentionAtActive[index] = isMentioned;
     this.setState({
-      unreadAtActive: unreadAtActive
+      unreadAtActive: unreadAtActive,
+      mentionAtActive: mentionAtActive
     });
     this.handleUnreadCountTotalChange();
   },
@@ -81,19 +85,24 @@ var MainPage = React.createClass({
       var allMentionCount = this.state.mentionCounts.reduce(function(prev, curr) {
         return prev + curr;
       }, 0);
+      this.state.mentionAtActive.forEach(function(state) {
+        if (state) {
+          allMentionCount += 1;
+        }
+      });
       this.props.onUnreadCountChange(allUnreadCount, allMentionCount);
     }
   },
-  handleNotify: function(index) {
+  handleNotify: function(index, isMentioned) {
     // Never turn on the unreadAtActive flag at current focused tab.
     if (this.state.key === index && remote.getCurrentWindow().isFocused()) {
       return;
     }
-    this.handleUnreadAtActiveChange(index, true);
+    this.handleUnreadAtActiveChange(index, true, isMentioned);
   },
   handleOnTeamFocused: function(index) {
     // Turn off the flag to indicate whether unread message of active channel contains at current tab.
-    this.handleUnreadAtActiveChange(index, false);
+    this.handleUnreadAtActiveChange(index, false, false);
   },
 
   visibleStyle: function(visible) {
@@ -124,8 +133,8 @@ var MainPage = React.createClass({
       var handleUnreadCountChange = function(unreadCount, mentionCount) {
         thisObj.handleUnreadCountChange(index, unreadCount, mentionCount);
       };
-      var handleNotify = function() {
-        thisObj.handleNotify(index);
+      var handleNotify = function(isMentioned) {
+        thisObj.handleNotify(index, isMentioned);
       };
       var handleNotificationClick = function() {
         thisObj.handleSelect(index);
@@ -197,9 +206,9 @@ var MattermostView = React.createClass({
     }
   },
 
-  handleNotify: function() {
+  handleNotify: function(isMentioned) {
     if (this.props.onNotify) {
-      this.props.onNotify();
+      this.props.onNotify(isMentioned);
     }
   },
 
@@ -260,7 +269,8 @@ var MattermostView = React.createClass({
           console.log(event.args[0]);
           break;
         case 'onActiveChannelNotify':
-          thisObj.handleNotify();
+          var isMentioned = event.args[0];
+          thisObj.handleNotify(isMentioned);
           break;
       }
     });
diff --git a/src/browser/webview/mattermost.js b/src/browser/webview/mattermost.js
index 9dcb088b..ade81305 100644
--- a/src/browser/webview/mattermost.js
+++ b/src/browser/webview/mattermost.js
@@ -24,25 +24,6 @@ var unreadCountTimer = setInterval(function() {
     }
   }
 
-  // unreadCount for active channel
-  var newSeparators = document.getElementsByClassName('new-separator');
-  var post;
-  for (var i = 0; i < newSeparators.length; i++) {
-    if (newSeparators[i].offsetParent !== null) {
-      post = newSeparators[i];
-    }
-  }
-  // mentionCount for active channel
-  if (post != null) {
-    while (post = post.nextSibling) {
-      var highlight = post.getElementsByClassName('mention-highlight');
-      if (highlight.length != 0 && highlight[0].offsetHeight != null) {
-        mentionCount++;
-        break;
-      }
-    }
-  }
-
   if (this.unreadCount != unreadCount || this.mentionCount != mentionCount) {
     ipc.sendToHost('onUnreadCountChange', unreadCount, mentionCount);
   }
@@ -80,6 +61,8 @@ function overrideNotificationWithBalloon() {
   Notification.prototype.close = function() {};
 };
 
+var lastUnread = {};
+
 // Show window even if it is hidden/minimized when notification is clicked.
 function overrideNotification() {
   Notification = function(title, options) {
@@ -89,8 +72,57 @@ function overrideNotification() {
     var activeChannel = document.querySelector('.active .sidebar-channel').text;
     console.log(activeChannel);
     console.log(title);
-    if (activeChannel === title) {
-      ipc.sendToHost('onActiveChannelNotify');
+
+    // mentionCount for active channel
+    var newSeparators = document.getElementsByClassName('new-separator');
+    var post;
+    var isMentioned = false;
+    // Skip until real new-separator appear.
+    for (var i = 0; i < newSeparators.length; i++) {
+      if (newSeparators[i].offsetParent !== null) {
+        post = newSeparators[i];
+      }
+    }
+
+    // If active channel is DM, all posts is treated as menion.
+    if (activeChannel === title + "×") {
+      isMentioned = true;
+    }
+    else {
+      // If active channel is CHANNEL, only .mention-highlight post is treated as mention.
+      if (post != null) {
+        // Skip posts until last unread.
+        if (activeChannel === title && lastUnread.channel === title && lastUnread.post !== null) {
+          var firstPost = post;
+          while (post = post.nextSibling) {
+            if (lastUnread.post === post.getAttribute('data-reactid')) {
+              break;
+            }
+          }
+          // Because last unread post not found, set first post.
+          if (post === null) {
+            post = firstPost;
+          }
+        }
+
+        while (post = post.nextSibling) {
+          var highlight = post.getElementsByClassName('mention-highlight');
+          if (highlight.length != 0 && highlight[0].offsetHeight != null) {
+            isMentioned = true;
+          }
+
+          // Remember last unread post.
+          if (post.nextSibling === null) {
+            lastUnread.post = post.getAttribute('data-reactid');
+            lastUnread.channel = title;
+          }
+        }
+      }
+    }
+
+    // Note: DM title is "{username}×". CHANNEL title is "{channel_title}".
+    if (activeChannel === title || activeChannel === title + "×") {
+      ipc.sendToHost('onActiveChannelNotify', isMentioned);
     }
   };
   Notification.requestPermission = function(callback) {