The Qinghai-XizangPlateau (QXP) plays a key role on both hydrological cycle and climate for southern and eastern Asia. It is important to simulate and analyze future climate condition over the QXP to investigate the distribution and evolution trend of ecosystems, climate and water resources for southeastern Asia. Based on ASD statistical downscaling model, climatic factors including precipitation and air temperature in the Yarlung Zangbo River (YZR) basin were downscaled to meteorological stations by using the MIROC3.2_medres data. Simulation accuracy was evaluated by comparing with the outputsof ERA-40 reanalysis. Future climate change scenarios in the periods of 2046-2065 and 2081-2100 were generated on the basis of ASD downscaling model. The results show that ASD can be applied to the YZR basin satisfactorily, being able to simulate the spatial and temporal patterns of precipitation and temperatureregimes, and the explained variance of temperature exceeds 90%, while the explained variance of precipitation reaches 12%~27%. Changes of annual total precipitation are not significant, the change trends are less than 5% for most of scenarios, but precipitation will become more concentrated. Precipitation in spring, autumn and winter decreases remarkably, with the largest ratio of 55.58%. Precipitation in summer, however, shows a significant increasing tendency. The largest amplitude is 30.44%. Temperature over the YZR basin will increase dramatically, the amplitude is 1.60~2.12℃ inthe middle of 21~(st) century, and 2.34~3.69℃at the end of 21~(st) century. It showed that water resources planning in the YZR basin will become a great challenge due to the changes of precipitation and air temperature in the future.