The grassland ecosystem of HulunBuir city is an important component of ecology security system in Northeast China. In this study, net primary productivity (NPP), as an improtant ecological parameter, was used to estmate the services value. Considering the characteristic of satellite imagery, it is difficult to calculate some functions. So we calculated the services value from 6 aspects, including soil erosion control, water conservation, direct production, gas regulation, nutrient recycling and atmospheric environment purification. The total services value of grassland ecosystem was estimated in RMB to be aproximately 18.47×109Yuan in 2006, the average economic value of unit area was 15.4×104Yuan/km2. The direct production value was 1.23×109Yuan/year; and the contribution rate to total value was 6.66%. The water regulation value was the maximum, 9.09×109Yuan/year. Gas regulation value was 5.25×109Yuan/yea. The purify atmosphere value was minimal.