diff --git a/a8/timer_attacher.h b/a8/timer_attacher.h
index 978e90e..64c99c1 100644
--- a/a8/timer_attacher.h
+++ b/a8/timer_attacher.h
@@ -28,6 +28,7 @@ namespace a8
         list_head timer_list_;
 
         friend class XTimer;
+        friend class XTimerImpl;
     };
 
 }
diff --git a/a8/xtimer.cc b/a8/xtimer.cc
index 62b95cc..8fa17d9 100644
--- a/a8/xtimer.cc
+++ b/a8/xtimer.cc
@@ -1,6 +1,7 @@
 #include <a8/a8.h>
 
 #include <a8/xtimer.h>
+#include <a8/timer_attacher.h>
 
 enum TimerType_e
 {
@@ -92,8 +93,6 @@ static int Cascade(struct xtvec_base *base, struct xtvec *tv, int index)
 
 namespace a8
 {
-    typedef struct list_head XTimerDestoryHandle;
-
     struct XTimerPtr
     {
         xtimer_list* timer = nullptr;
@@ -109,8 +108,9 @@ namespace a8
     {
     public:
 
-        XTimerImpl()
+        XTimerImpl(XTimer* owner)
         {
+            owner_ = owner;
             base_ = new xtvec_base();
             base_->running_timer = nullptr;
             INIT_LIST_HEAD(&base_->free_timer);
@@ -176,6 +176,12 @@ namespace a8
                           expire_time,
                           cb
                           );
+            if (attacher) {
+                if (attacher->owner_ != owner_) {
+                    abort();
+                }
+                list_add_tail(&timer->attach_entry, &attacher->timer_list_);
+            }
             InternalModifyTime(timer, expire_time);
             if (wp) {
                 AddTimerWp(timer, *wp);
@@ -190,6 +196,12 @@ namespace a8
                           get_tick_count_func_(context_) + expire_time,
                           expire_time,
                           cb);
+            if (attacher) {
+                if (attacher->owner_ != owner_) {
+                    abort();
+                }
+                list_add_tail(&timer->attach_entry, &attacher->timer_list_);
+            }
             InternalModifyTime(timer, expire_time);
             if (wp) {
                 AddTimerWp(timer, *wp);
@@ -260,11 +272,22 @@ namespace a8
 
         void ClearAttacher(Attacher* attacher)
         {
-
+            struct list_head* pos = nullptr;
+            struct list_head* n = nullptr;
+            list_for_each_safe(pos, n, &attacher->timer_list_) {
+                xtimer_list* tmp_timer = list_entry(pos, struct xtimer_list, attach_entry);
+                InternalDelete(tmp_timer, false, true);
+            }
         }
 
         void DestoryAttacher(Attacher* attacher)
         {
+            struct list_head* pos = nullptr;
+            struct list_head* n = nullptr;
+            list_for_each_safe(pos, n, &attacher->timer_list_) {
+                xtimer_list* tmp_timer = list_entry(pos, struct xtimer_list, attach_entry);
+                InternalDelete(tmp_timer, true, true);
+            }
         }
 
         void UpdateTimer()
@@ -369,24 +392,12 @@ namespace a8
             free_timers(&base_->free_timer);
         }
 
-        XTimerDestoryHandle* AddTimerDestoryHandle(std::weak_ptr<XTimerPtr>& timer_ptr,
-                                                           std::function<void(xtimer_list*)> cb)
+        void AddTimerDestoryHandle(std::weak_ptr<XTimerPtr>& timer_ptr,
+                                   std::function<void(xtimer_list*)> cb)
         {
             XTimerDestoryHandleNode* node = new XTimerDestoryHandleNode;
-            node->cb = cb;
+            node->cb = std::move(cb);
             list_add_tail(&node->entry, &timer_ptr.lock()->timer->destory_handle_list);
-            return &node->entry;
-        }
-
-        void RemoveTimerDestoryHandle(XTimerDestoryHandle* handle)
-        {
-            if (!handle || list_empty(handle)) {
-                abort();
-            }
-
-            XTimerDestoryHandleNode* node = list_entry(handle, XTimerDestoryHandleNode, entry);
-            list_del_init(&node->entry);
-            delete node;
         }
 
         void InitTimerList(xtimer_list* timer,
@@ -414,6 +425,7 @@ namespace a8
         }
 
     private:
+        XTimer* owner_ = nullptr;
         xtvec_base* base_ = nullptr;
         XGetTickCountFunc get_tick_count_func_ = nullptr;
         void* context_ = nullptr;
@@ -423,7 +435,7 @@ namespace a8
 
     XTimer::XTimer()
     {
-        impl_ = new XTimerImpl();
+        impl_ = new XTimerImpl(this);
     }
 
     XTimer::~XTimer()
@@ -529,11 +541,17 @@ namespace a8
 
     void XTimer::ClearAttacher(Attacher* attacher)
     {
+        if (attacher->owner_ != this) {
+            abort();
+        }
         impl_->ClearAttacher(attacher);
     }
 
     void XTimer::DestoryAttacher(Attacher* attacher)
     {
+        if (attacher->owner_ != this) {
+            abort();
+        }
         impl_->DestoryAttacher(attacher);
     }