The rapid development of Internet banking has led to the deposit moving, banking reform and monetary fund development, which are not only changing the pattern of the financial markets, but also having an impact on monetary policy. From the influence of Internet financial mechanism of monetary policy, this paper analyzes the current money demand, money supply and efficiency of monetary policy. It has made the following three conclusions. First, the Internet can promote the publics investment motivation and increase the money demand. Second, the Internet banking can broaden the money supply and reduce the money supplys controllability, predictability and relevance. Third, the Internet banking disturbs the accuracy of monetary policy making and the effectiveness of monetary policy implementation.