The mass change of the Antarctica ice sheet reflects global climate change,and can influence the global sea level directly.Since 2003 the ice,cloud and land elevation satellite (ICESat)laser altimetry mission has provided satellite altimetry data over the Antarctic up to 86°S.One of the primary missions of ICESat is to determine the change in the polar ice sheet and to assess the impact on global sea level.To better understand the effect of Antarctic ice sheet on the global sea level,this work uses the ICESat data to analyze the mass change of the Antarctic ice sheet. There are two methods for calculating the mass change of the Antarctic ice sheet using altimetry satellite data:cross point method and repeat track method.The repeat track method seems more commonly applied,in which the unmeasured topography between near repeat tracks need to be considered when comparing elevations from different tracks.We applied slope corrections between the different tracks to restrict all the different tracks to one reference track, and then calculated the surface elevation changes of the Antarctic ice sheet.The mass change of the Antarctic ice sheet was estimated by using the ice density model. The mass balance of Antarctic ice sheet was calculated to be-4421Gt/a including-26 6Gt/a for West Antarctica and-1820Gt/a for East Antarctica using 5-year ICESat altimetry data from October 2003 to December 2008,and the contribution of the Antarctic ice sheet loss to global sea level is about 0.12 mm?a~(-1). The comparison of our results with previous work shows a strong agreement.The results show that the mass losing of the Antarctic ice sheet is mainly concentrated near the Amundsen Sea in West Antarctica and Poinsett Cape in East Antarctica.