Abstract: An adequate decorrelation filter is chosen for GRGS GL04 data after comparing different decorrelation filters in the form of the polynomial with different order. The spatial distribution of the ice mass change in Greenland ice sheet is estimated during July 2002 to September 2007,and the change rate of -116±9 km3/a is also given. The corresponding contribution to the sea level change is about 0.32±0.02 mm/a.