In this study, the aboveground biomass (AGB) was estimated for the forest in Xishuangbanna (Southwestern China) area by combining forest field investigation data and Geoscience Laser Altimeter System (GLAS) data, onboard the Ice, Cloud and land Elevation Satellite (ICESat). The tree height prediction models at GLAS footprint level were developed from GLAS waveform variables and filed survey plot tree height using multiple linear stepwise regression method, and then were used to estimate the biomass for all GLAS footprints of forest in the study area according the allometric equations deduced by the fixed field sites. The AGB estimate result was in a reasonable range after compared with the forest inventory plot data.