Hi, all， My code looks like this: ============================================================= // M is a class, m_show() is one of its methods. void test_boost_thread_1(){ M p(88); boost::thread pthd(boost::bind(&M::m_show, &p)); } void test_boost_thread_2(){ M p(99); boost::thread pthd(boost::bind(&M::m_show, &p)); } =============================================================== "test_boost_thread_1()" and "test_boost_thread_2()" are running at the same time ,but I find that the output is wrong. If I changed the thread name "pthd" in "test_boost_thread_()" to other name , not "pthd" , it looks ok. why ? ........ Now , many other threads want to run " test_boost_thread_1() " at the "same" time, How could I make it ok ? Thanks for your time. Best Regards.