Modern economy depends on money,but money is created by the bank system.So,as the main body of finance institution in one state,banks have the importance influence upon the economy of one country.Center bank constitutes the money policy and executes the money policy in one country,then it is the core of the whole financial system.But the validity for the money policy must rely on the activity of commercial banks to the money policy.Being based on the money policy transmitting mechanism,this Article analyzes how to establish a kind of bargain relation between Center bank and commercial bank so that commercial bank may work hard toward the aim of the money policy for the center bank under the asymmetric information,which was the bases of the Commercial Banks' innovation.