This paper use narrow money to GDP ratio，broad money to GDP ratio，and domestic credit to GDP ratio to measure the extent of excess liquidity，which concludes that there is excess liquidity in the developed countries such as United States and Japan，and in the emerging market economies such as China，Taiwan，Hong Kong，and South Korea.The roots of excess liquidity in developed counties lie in that those governments applied loose monetary policies in which low interest rates played an important role.The roots of excess liquidity in emerging market economies are the increase of base money caused by the accumulation of foreign exchange reserves.The international transfer mechanism of liquidity depicts the characteristics of current center periphery international monetary system.Excess liquidity has already caused the asset bubbles over the world，and maybe cause the high inflation in the future.Once the excess liquidity reverses to liquidity crunch，the world economy and financial system will face serious negative impact.