diff --git a/hwe/css/msg.css b/hwe/css/msg.css
index bddc7f7c..ddb00405 100644
--- a/hwe/css/msg.css
+++ b/hwe/css/msg.css
@@ -87,6 +87,7 @@
     font-weight: bold;
     margin-bottom:3px;
     color:white;
+    position: relative;
 }
 
 .message_input_form{
@@ -141,6 +142,10 @@
     height: 1.2em;
 }
 
+.msg_invalid{
+    color:rgba(255,255,255,0.5);
+}
+
 .msg_body{
     padding-left:64px;
 }
@@ -153,6 +158,14 @@
     border-radius: 3px;
 }
 
+.btn-delete-msg{
+    position: absolute;
+    right: 0;
+    top: 0;
+    margin:2px 2px 0 2px;
+    font-size:8px;
+}
+
 /*
 .public_message .msg_target{
     box-shadow: 2px 2px darkslategrey;
diff --git a/hwe/index.php b/hwe/index.php
index 3c65e8f8..ee51383b 100644
--- a/hwe/index.php
+++ b/hwe/index.php
@@ -88,6 +88,7 @@ $mapTheme = $admin['map_theme'];
 <?=WebUtil::printJS('../e_lib/jquery-3.3.1.min.js')?>
 <?=WebUtil::printJS('../e_lib/jquery.redirect.js')?>
 <?=WebUtil::printJS('../e_lib/bootstrap.bundle.min.js')?>
+<?=WebUtil::printJS('../e_lib/moment.min.js')?>
 <?=WebUtil::printJS('../d_shared/common_path.js')?>
 <?=WebUtil::printJS('js/common.js')?>
 <?=WebUtil::printJS('js/main.js')?>
diff --git a/hwe/j_msg_delete.php b/hwe/j_msg_delete.php
new file mode 100644
index 00000000..15a680b8
--- /dev/null
+++ b/hwe/j_msg_delete.php
@@ -0,0 +1,72 @@
+<?php
+namespace sammo;
+
+include('lib.php');
+include('func.php');
+
+$session = Session::requireGameLogin([]);
+$userID = Session::getUserID();
+
+$msgID = Util::getReq('msgID', 'int');
+if($msgID === null){
+    Json::die([
+        'result'=>false,
+        'reason'=>'올바르지 않은 범위 입니다.'
+    ]);
+}
+
+$lastMsgGet = Json::decode($session->lastMsgGet)??[];
+$now = new \DateTime();
+$delayTime = false;
+if(count($lastMsgGet) >= 10){
+    try{
+        if($lastMsgGet[0] !== 'string'){
+            throw new \Exception('Why not string?');
+        }
+        $first = new \DateTime($lastMsgGet[0]);
+        $diff = $first->diff($now);
+        if($diff->days == 0 && $diff->h > 0 && $diff->i == 0 && $diff->s <= 5){
+            $delayTime = true;
+        }
+        array_shift($lastMsgGet);
+    }
+    catch(\Exception $e){
+        $lastMsgGet = [];
+    } 
+}
+$lastMsgGet[] = $now;
+$session->lastMsgGet = Json::encode($lastMsgGet);
+
+if($delayTime){
+    sleep(1);
+}
+$session->setReadOnly();
+
+list($generalID, $nationID, $generalName) = DB::db()->queryFirstList(
+    'select `no`, `nation`, `name` from `general` where owner = %i',
+    $userID
+);
+
+if($nationID === null){
+    Json::die([
+        'result'=>false,
+        'reason'=>'장수가 사망했습니다.'
+    ]);
+}
+
+$reason = Message::deleteMsg($msgID, $generalID);
+if($reason === null){
+    $result = [
+        'result'=>true,
+        'reason'=>'success'
+    ];
+}
+else{
+    $result = [
+        'result'=>false,
+        'reason'=>$reason
+    ];
+}
+
+
+Json::die($result);
\ No newline at end of file
diff --git a/hwe/j_msg_get_old.php b/hwe/j_msg_get_old.php
index 0cb2b825..0c7b6d54 100644
--- a/hwe/j_msg_get_old.php
+++ b/hwe/j_msg_get_old.php
@@ -10,7 +10,7 @@ $userID = Session::getUserID();
 $reqTo = Util::getReq('to', 'int');
 $reqType = Util::getReq('type', 'string');
 
-if(!$reqTo === null){
+if($reqTo === null){
     Json::die([
         'result'=>false,
         'reason'=>'올바르지 않은 범위 입니다.'
diff --git a/hwe/js/msg.js b/hwe/js/msg.js
index 55396f6f..1cc1bce0 100644
--- a/hwe/js/msg.js
+++ b/hwe/js/msg.js
@@ -47,6 +47,17 @@ function responseMessage(msgID, response){
     }).then(refreshMsg);
 }
 
+function deleteMessage(msgID){
+    $.ajax({
+        url: 'j_msg_delete.php',
+        type: 'post',
+        dataType:'json',
+        data: {
+            msgID:msgID
+        }
+    }).then(refreshMsg);
+}
+
 function refreshMsg(result){
     if(result && !result.result){
         alert(result.reason);
@@ -79,6 +90,18 @@ function showOldMsg(msgType){
 }
 
 function redrawMsg(deferred, addFront){
+    function checkErasable(obj){
+
+        var now = moment().format('YYYY-MM-DD HH:mm:ss');
+        $('.btn-delete-msg').each(function(){
+            var $btn = $(this);
+            var eraseUntil = $btn.data('erase_until');
+            if(eraseUntil < now){
+                $btn.detach();
+            }
+        })
+        return obj;
+    }
     function checkClear(obj){
         if(!obj.result){
             var t = $.Deferred();
@@ -167,6 +190,7 @@ function redrawMsg(deferred, addFront){
 
             var needRefreshLastContact = (msgType == 'private');
 
+            var now = moment().format('YYYY-MM-DD HH:mm:ss');
             //list의 맨 앞이 가장 최신 메시지임.
             var $msgs = msgSource.map(function(msg){
 
@@ -199,6 +223,15 @@ function redrawMsg(deferred, addFront){
                 else{
                     msg.allowButton = true;
                 }
+                msg.myGeneralID = myGeneralID;
+                msg.last5min = moment(msg.time).add(5, 'minute').format('YYYY-MM-DD HH:mm:ss');
+                msg.now = now;
+                if(msg.option && msg.option.invalid){
+                    msg.invalidType = 'msg_invalid';
+                }
+                else{
+                    msg.invalidType = 'msg_valid';
+                }
                 var msgHtml = TemplateEngine(messageTemplate, msg);
                 
 
@@ -212,11 +245,39 @@ function redrawMsg(deferred, addFront){
                     $msg = $existMsg;
                 }
 
-                if(msg.option && msg.option.parent){
-                    //parent는 삭제.
-                    $('#msg_{0}'.format(msg.option.parent)).detach();
+                var hideMsg = false;
+                if(msg.option){
+                    console.log(msg.option);
+                    if(msg.option.delete !== undefined){
+                        //delete는 삭제.
+                        $('#msg_{0}'.format(msg.option.delete)).detach();
+                    }
+                    if(msg.option.overwrite !== undefined){
+                        //overwrite는 숨기기.
+                        $.map(msg.option.overwrite, function (overwriteID) {
+                            console.log(overwriteID);
+                            var $msg = $('#msg_{0}'.format(overwriteID));
+                            $msg.find('.btn-delete-msg').detach();
+                            $msg.find('.msg_content').html('삭제된 메시지입니다.').removeClass('msg_valid').addClass('msg_invalid');
+                        });
+                        
+                    }
+                    if(msg.option.hide){
+                        hideMsg = true;
+                    }
                 }
 
+                if(hideMsg){
+                    return null;
+                }
+
+                $msg.find('.btn-delete-msg').click(function(){
+                    if(!confirm("삭제하시겠습니까?")){
+                        return false;
+                    }
+                    deleteMessage(msg.id);
+                });
+
                 $msg.find('button.prompt_yes').click(function(){
                     if(!confirm("수락하시겠습니까?")){
                         return false;
@@ -253,6 +314,7 @@ function redrawMsg(deferred, addFront){
     }
 
     deferred
+        .then(checkErasable)
         .then(checkClear)
         .then(registerSequence)
         .then(refineMessageObjs)
@@ -459,7 +521,7 @@ function activateMessageForm(){
 jQuery(function($){
 
     //tmp_template.html은 추후 msg.js에 통합될 수 있음
-    var getTemplate = $.get('js/templates/message.html?3',function(obj){
+    var getTemplate = $.get('js/templates/message.html?7',function(obj){
         messageTemplate = obj;
     });
 
diff --git a/hwe/js/templates/message.html b/hwe/js/templates/message.html
index 58c7e386..d4b2d9af 100644
--- a/hwe/js/templates/message.html
+++ b/hwe/js/templates/message.html
@@ -12,6 +12,9 @@
     </div>
     <div class="msg_body">
         <div class="msg_header">
+            <%if(msgType != 'diplomacy' && src.id == myGeneralID && now <= last5min && invalidType == 'msg_valid'){%>
+                <button type="button" data-erase_until="<%last5min%>" class="btn btn btn-outline-warning btn-sm btn-delete-msg" style='float:right'>❌</button>
+            <%}%>
             <%if(msgType == 'private') {%>
                 <%if(src.name == generalName){%>
                 <span class="msg_target msg_<%src.colorType%>" style="background-color:<%src.color%>;">나</span
@@ -37,9 +40,8 @@
                 <span class="msg_target msg_<%src.colorType%>" style="background-color:<%src.color%>;"><%e(src.name)%>:<%src.nation%></span>
             <%} %>
             <span class="msg_time">&lt;<%e(time)%>&gt;</span>
-        </div>
-
-        <div class="msg_content"><%e(text)%></div>
+        </div>        
+        <div class="msg_content <%invalidType%>"><%e(text)%></div>
         <%if(this.option && this.option.action) {%>
         <div class="msg_prompt">
             <button class="prompt_yes btn_prompt" <%allowButton?'':'disabled="disabled"'%>>>수락</button> <button class="prompt_no btn_prompt" <%allowButton?'':'disabled="disabled"'%>>거절</button>
diff --git a/hwe/sammo/DiplomaticMessage.php b/hwe/sammo/DiplomaticMessage.php
index 7464ed30..491d323d 100644
--- a/hwe/sammo/DiplomaticMessage.php
+++ b/hwe/sammo/DiplomaticMessage.php
@@ -333,7 +333,6 @@ class DiplomaticMessage extends Message{
         $this->dest->generalID = $receiverID;
         $this->dest->generalName = $general['name'];
         $this->msgOption['used'] = true;
-        $this->invalidate();
         $this->validDiplomacy = false;
 
         $josaYi = JosaUtil::pick($this->src->nationName, '이');
@@ -345,9 +344,11 @@ class DiplomaticMessage extends Message{
             new \DateTime(),
             new \DateTime('9999-12-31'),
             [
-                'delete'=>$this->id
+                'delete'=>$this->id,
+                'silence'=>true,
             ]
         );
+        $this->invalidate();
         $newMsg->send();
 
         return self::ACCEPTED;
diff --git a/hwe/sammo/Message.php b/hwe/sammo/Message.php
index 2bef1b1e..dfef9c98 100644
--- a/hwe/sammo/Message.php
+++ b/hwe/sammo/Message.php
@@ -184,7 +184,7 @@ class Message
         return false;
     }
 
-    public static function getMessageByID(int $messageID) : Message
+    public static function getMessageByID(int $messageID) : ?Message
     {
         $db = DB::db();
         $now = new \DateTime();
@@ -265,6 +265,53 @@ class Message
         }, $db->query('SELECT * FROM `message` WHERE %l ORDER BY id DESC %? ', $where, $limitSql));
     }
 
+    public static function deleteMsg(int $msgID, int $generalID):?string{
+        $msgObj = static::getMessageByID($msgID);
+        if($msgObj=== null){
+            return '메시지가 없습니다';
+        }
+
+        if($msgObj->src->generalID != $generalID){
+            return '본인의 메시지만 삭제할 수 있습니다.';
+        }
+
+        $prev5min = new \DateTime();
+        $prev5min->sub(new \DateInterval('PT5M'));
+
+        if($msgObj->date < $prev5min){
+            return '5분 이내의 메시지만 삭제할 수 있습니다.';
+        }
+
+        $msgOption = [
+            'hide'=>true,   
+            'silence'=>true,
+            'overwrite'=>[$msgObj->id]
+        ];
+
+        if($msgObj->msgType == Message::MSGTYPE_PRIVATE || $msgObj->msgType == Message::MSGTYPE_NATIONAL){
+            $msgObj2 = static::getMessageByID($msgObj->msgOption['receiverMessageID']);
+            if($msgObj2 !== null){
+                $msgObj2->invalidate(null, false);
+                $msgOption['overwrite'][] = [$msgObj2->id];
+            }
+        }
+
+        $in1min = new \DateTime();
+        $in1min->add(new \DateInterval('PT1M'));
+        $newMsg = new Message(
+            $msgObj->msgType, 
+            $msgObj->src, 
+            $msgObj->dest, 
+            "req_del_msg",
+            new \DateTime(),
+            $in1min,
+            $msgOption
+        );
+        $msgObj->invalidate(null, false);
+        $newMsg->send(false);
+        return null;
+    }
+
     protected function sendRaw(int $mailbox):array{
         //NOTE:: 여기선 검증하지 않는다.
 
@@ -302,7 +349,7 @@ class Message
     }
 
     private function sendToSender():array{
-        if($this->sendCnt > 0){
+        if($this->sendCnt > 1){
             throw new \RuntimeException('이미 전송한 메일입니다.');
         }
         if($this->msgType === self::MSGTYPE_PRIVATE && $this->src->generalID !== $this->dest->generalID){
@@ -315,15 +362,17 @@ class Message
     }
 
     private function sendToReceiver() : array{
-        if($this->sendCnt > 1 || $this->isInboxMail){
+        if($this->sendCnt > 0 || $this->isInboxMail){
             throw new \RuntimeException('이미 전송한 메일입니다.');
         }
 
         if($this->msgType === self::MSGTYPE_PRIVATE){
-            //XXX: 알림을 이런식으로 보내는게 맞는가에 대한 의문 있음
-            DB::db()->update('general', [
-                'newmsg'=>1
-            ], 'no=%i',$this->dest->generalID);
+            if(!($this->msgOption['silence']??false)){
+                //XXX: 알림을 이런식으로 보내는게 맞는가에 대한 의문 있음
+                DB::db()->update('general', [
+                    'newmsg'=>1
+                ], 'no=%i',$this->dest->generalID);
+            }
             return $this->sendRaw($this->dest->generalID);
         }
 
@@ -339,18 +388,7 @@ class Message
     }
 
     public function send(bool $sendDestOnly=false):int{
-        if(!$sendDestOnly){
-            list($senderMailbox, $sendID) = $this->sendToSender();
-            if($sendID){
-                $this->mailbox = $senderMailbox;
-                $this->isInboxMail = false;
-                $this->id = $sendID;
-                $this->msgOption['senderMessageID'] = $sendID;
-                $this->sendCnt = 1;
-            }
-        }
-        
-        list($receiverMailbox, $receiveID) = $this->sendToReceiver();
+        [$receiverMailbox, $receiveID] = $this->sendToReceiver();
         if(!$receiveID && !$sendDestOnly){
             return $sendID;
         }
@@ -358,17 +396,39 @@ class Message
         $this->isInboxMail = true;
         $this->id = $receiveID;
         $this->msgOption['receiverMessageID'] = $receiveID;
-        $this->sendCnt = 2;
+        $this->sendCnt = 1;
+
+        if(!$sendDestOnly){
+            [$senderMailbox, $sendID] = $this->sendToSender();
+            if($sendID){
+                $this->mailbox = $senderMailbox;
+                $this->isInboxMail = false;
+                $this->id = $sendID;
+                $this->msgOption['senderMessageID'] = $sendID;
+                $this->sendCnt = 2;
+            }
+        }
         
         return $receiveID;
     }
 
-    public function invalidate(array $newMsgOption=null){
+    public function invalidate(?array $newMsgOption=null, bool $hideMsg=true){
         if($newMsgOption !== null){
             $this->msgOption = $newMsgOption;
         }
 
-        $this->validUntil = new \DateTime('2000-12-31');
+        $this->msgOption['invalid'] = true;
+
+        if($hideMsg){
+            $this->validUntil = new \DateTime('2000-12-31');
+        }
+        else{
+            if(key_exists('receiverMessageID', $this->msgOption)){
+                $this->msgOption['originalText'] = $this->msg;
+            }
+            $this->msg = '삭제된 메시지입니다.';
+        }
+        
         
         $db = DB::db();
         $db->update('message', [