After entering the 21st century，Japan adopted the quantitative easing（QE） monetary policy firstly，especially the Andouble government implemented the QQE to fight domestic deflation and recover economy. This paper analyses the evolution and characteristics of the quantitative easing monetary policy in Japan，and the conclusion obtained by a VAR model is：In the short term，Japan’s quantitative easing monetary policy is conducive to the stability of the financial system，has positive effects of asset allocation and the market anticipation. But in the long run，the effects of raising prices，promoting consumption and stimulating the real economy are limited，and pave the way for inflation and financial crisis in Japan.