his article is aimed at make a comprehensive analysis on the buckling—restrained braced. The paper summarized the research of BRB in recent years both at home and abroad.The stress mechanism of such brace has been studied at first, and then some new forms of such braces are intro—duced.And modeling in different common software also been given.At last, analyzed reasons of not been able to used widely in our country.All of the work is hoping to make a full understanding of the new form of brace for the engineers.