The influence of the different melting rate of Greenland ice sheet on sea level of the global and regional ocean are studied based on POP model under the RCP4.5scenario for the 21st century.In the 21st century,the low melting rate of Greenland ice sheet has small influence on the global and regional sea level variations,which mainly due to the meridional overturning flow doesnt weak under the low melting rate of Greenland ice sheet in the Atlantic. The high melting rate will have notably effect on the dynamic and steric sea level in the Atlantic,the Arctic and Antarctic Circumpolar Current(ACC).The dynamic sea level will significantly rise in the north Atlantic subpolar Ocean,tropical Atlantic Ocean,the south Atlantic subtropical and Arctic Ocean,which will rise fast in ocean of southern Greenland and along the coast of North America,that is due to notable weakened of the meridional overturning flow caused by strengthen stratification of the upper ocean and deep convection weakened because of a lot of fresh water input Greenland nearby ocean in the high rate of melting of Greenland ice sheet,namely the labrad or current will strengthen,the Gulf Stream and the north Atlantic current weakened.The thermosteric sea level will significantly decline in the Arctic ocean,the ocean of the southern Greenland and the Atlantic subtropical ocean, while which obviously rise the tropical Atlantic ocean and the Gulf Stream.Meanwhile the halosteric sea level change will be opposite to the thermosteric sea level.The steric sea level showed change due to the water is cooling and thin in the north Atlantic subpolar ocean,the weakened of the Atlantic meridional overturning flow and thermohaline circulation caused by input of lot of low temperature and low salt water in the 21st century.