Abstract: A 360 order gravity field model WDM94 has been established based on the Chinese topography and its own gravity data combined with the world wide data.A Chinese new quasi geoid CQG2000 with dm level accuracy has been determined with the Chinese GPS/leveling network,land gravity data,and altimetry data.CQG2000 covers the all Chinese territory,land and ocean.The merge of the land geoid and ocean geoid in China has been carefully studied and completed successfully.Besides,the local geoids with cm magnitude accuracy level in Jiangsu,Hainan,Shenzhen,Dalian and the west wing of "South Water Towards the North" are also determined.For the further utilization of the quasi geoid in mapping the "GPS-Mapping Software and Hardware in a Whole System" has been studied and compiled.