The simulation of climate in East Asia region in 15 years were carried out by the RegCM3 nested into ERA40 re-analysis data.The simulation of the temperature and precipitation distribution and changes over Qinghai-Xizang Plateau and along the Qinghai-Xizang Railway were mainly investigated.The results show that RegCM3 model has ability to simulate the basic character of the spatial distribution of precipitation and temperature over Qinghai-Xizang Plateau and along the railway region.At same time,the model simulation can provid more reliable information of local precipitation and air temperature for the region of rare observation station.The model can reproduce well the precipitation along Qinghai-Xizang railway,especially the change trend of air temperature in each month of a year.The annual change of air temperature in the region is well simulated,but the simulated ability to the annual change of precipitation in this region remain to be improved.