Using LARS-WG downscaling method, CNCM3、HADCM3 and IPCM4 are selected out from 15 GCMs in the IPCC Fourth Assessment Report based on the performance in simulating precipitation and temperature in Biliuhe Reservoir basin. Futurechanges of precipitation and temperature are evaluated under A2, A1B and B1 scenarios, while future change of runoff is evaluatedby using ABCD model, the results of which can help provide the basis for water resources planning and management. The resultshows that CNCM3、HADCM3 and IPCM4 stand out in simulating precipitation and temperature in Biliuhe Reservoir basin.Compared with baseline period, the relative change of future annual average rainfall will be -6.4%~3.7%; future annual averagetemperature will increase 0.8℃~1.2℃; the relative change of future potential evaporation will increase 2.4%~4.3%; range of futureannual average runoff will be 4.8~6.2 （108m3）, decreasing by -4.7%~-27.1%. Greater challenges will be faced in future utilizationof water resources.