diff --git a/app/Models/Topic.php b/app/Models/Topic.php
index a3d6d3c..8be0669 100644
--- a/app/Models/Topic.php
+++ b/app/Models/Topic.php
@@ -7,7 +7,7 @@ class Topic extends Model
     protected $fillable = ['title', 'category_id', 'body', 'excerpt', 'slug'];
 
 
-    public function link($params)
+    public function link($params = [])
     {
         return route('topics.show', array_merge([$this->id, $this->slug], $params));
     }
diff --git a/app/Observers/ReplyObserver.php b/app/Observers/ReplyObserver.php
index 61c35f1..ff43273 100644
--- a/app/Observers/ReplyObserver.php
+++ b/app/Observers/ReplyObserver.php
@@ -28,4 +28,9 @@ class ReplyObserver
             $topic->user->notify(new TopicReplied($reply));
         }
     }
+
+    public function deleted(Reply $reply)
+    {
+        $reply->topic->decrement('reply_count', 1);
+    }
 }
\ No newline at end of file
diff --git a/app/Observers/TopicObserver.php b/app/Observers/TopicObserver.php
index b3fe8ad..6673de1 100644
--- a/app/Observers/TopicObserver.php
+++ b/app/Observers/TopicObserver.php
@@ -33,4 +33,9 @@ class TopicObserver
     {
         //
     }
+
+    public function deleted(Topic $topic)
+    {
+        \DB::table('replies')->where('topic_id', $topic->id)->delete();
+    }
 }
\ No newline at end of file
diff --git a/app/Policies/ReplyPolicy.php b/app/Policies/ReplyPolicy.php
index cd54110..242e379 100644
--- a/app/Policies/ReplyPolicy.php
+++ b/app/Policies/ReplyPolicy.php
@@ -15,6 +15,6 @@ class ReplyPolicy extends Policy
 
     public function destroy(User $user, Reply $reply)
     {
-        return true;
+        return $user->isAuthorOf($reply) || $user->isAuthorOf($reply->topic);
     }
 }
diff --git a/resources/views/topics/_reply_list.blade.php b/resources/views/topics/_reply_list.blade.php
index f67ec7e..036e4b1 100644
--- a/resources/views/topics/_reply_list.blade.php
+++ b/resources/views/topics/_reply_list.blade.php
@@ -17,11 +17,17 @@
                     <span class="meta" title="{{ $reply->created_at }}">{{ $reply->created_at->diffForHumans() }}</span>
 
                     {{-- 回复删除按钮 --}}
-                    <span class="meta pull-right">
-                        <a title="删除回复">
-                        <span class="glyphicon glyphicon-trash" aria-hidden="true"></span>
-                        </a>
-                    </span>
+                    @can('destroy',$reply)
+                        <span class="meta pull-right">
+                            <form action="{{route('replies.destroy',$reply->id)}}" method="post">
+                                {{csrf_field()}}
+                                {{method_field('DELETE')}}
+                                <button type="submit" class="btn btn-default btn-xs pull-left">
+                                    <i class="glyphicon glyphicon-trash"></i>
+                                </button>
+                            </form>
+                        </span>
+                    @endcan
                 </div>
                 <div class="reply-content">
                     {!! $reply->content !!}