diff --git a/src/thread.c b/src/thread.c
index 0f0265fc354d8241aecf051d0cd9d913833bb733..9e5c97983b91a5cf32b28ec4aea5fd7693b6889e 100644
--- a/src/thread.c
+++ b/src/thread.c
@@ -275,6 +275,7 @@ rt_err_t rt_thread_startup(rt_thread_t thread)
     /* thread check */
     RT_ASSERT(thread != RT_NULL);
     RT_ASSERT((thread->stat & RT_THREAD_STAT_MASK) == RT_THREAD_INIT);
+    RT_ASSERT(rt_object_get_type((rt_object_t)thread) == RT_Object_Class_Thread);
 
     /* set current priority to init priority */
     thread->current_priority = thread->init_priority;
@@ -318,6 +319,8 @@ rt_err_t rt_thread_detach(rt_thread_t thread)
 
     /* thread check */
     RT_ASSERT(thread != RT_NULL);
+    RT_ASSERT(rt_object_get_type((rt_object_t)thread) == RT_Object_Class_Thread);
+    RT_ASSERT(rt_object_is_systemobject((rt_object_t)thread));
 
     if ((thread->stat & RT_THREAD_STAT_MASK) != RT_THREAD_INIT)
     {
@@ -416,6 +419,8 @@ rt_err_t rt_thread_delete(rt_thread_t thread)
 
     /* thread check */
     RT_ASSERT(thread != RT_NULL);
+    RT_ASSERT(rt_object_get_type((rt_object_t)thread) == RT_Object_Class_Thread);
+    RT_ASSERT(rt_object_is_systemobject((rt_object_t)thread) == RT_FALSE);
 
     if ((thread->stat & RT_THREAD_STAT_MASK) != RT_THREAD_INIT)
     {
@@ -504,6 +509,7 @@ rt_err_t rt_thread_sleep(rt_tick_t tick)
     /* set to current thread */
     thread = rt_current_thread;
     RT_ASSERT(thread != RT_NULL);
+    RT_ASSERT(rt_object_get_type((rt_object_t)thread) == RT_Object_Class_Thread);
 
     /* suspend thread */
     rt_thread_suspend(thread);
@@ -572,6 +578,7 @@ rt_err_t rt_thread_control(rt_thread_t thread, int cmd, void *arg)
 
     /* thread check */
     RT_ASSERT(thread != RT_NULL);
+    RT_ASSERT(rt_object_get_type((rt_object_t)thread) == RT_Object_Class_Thread);
 
     switch (cmd)
     {
@@ -650,6 +657,7 @@ rt_err_t rt_thread_suspend(rt_thread_t thread)
 
     /* thread check */
     RT_ASSERT(thread != RT_NULL);
+    RT_ASSERT(rt_object_get_type((rt_object_t)thread) == RT_Object_Class_Thread);
 
     RT_DEBUG_LOG(RT_DEBUG_THREAD, ("thread suspend:  %s\n", thread->name));
 
@@ -692,6 +700,7 @@ rt_err_t rt_thread_resume(rt_thread_t thread)
 
     /* thread check */
     RT_ASSERT(thread != RT_NULL);
+    RT_ASSERT(rt_object_get_type((rt_object_t)thread) == RT_Object_Class_Thread);
 
     RT_DEBUG_LOG(RT_DEBUG_THREAD, ("thread resume:  %s\n", thread->name));
 
@@ -737,6 +746,7 @@ void rt_thread_timeout(void *parameter)
     /* thread check */
     RT_ASSERT(thread != RT_NULL);
     RT_ASSERT((thread->stat & RT_THREAD_STAT_MASK) == RT_THREAD_SUSPEND);
+    RT_ASSERT(rt_object_get_type((rt_object_t)thread) == RT_Object_Class_Thread);
 
     /* set error number */
     thread->error = -RT_ETIMEOUT;