Abstract: Stable isotopes of precipitation are directly related to the moisture sources. This effect has potential impact on the stable isotopic record from ice cores on the Tibetan Plateau. A net work of stable isotopes of precipitation has been set up in West China in recent years. The spatial and seasonal variations of both δ18 O and d-excess of precipitation in different parts of West China are monitored to calcify the impact of moisture sources related to the atmospheric circulation.The result shows that there is a large spatial difference on δ18 O and d-excess of precipitation, which is largely caused by the northward intrusion of southeast monsoon in summer to the Tanggula Mts. For the seasonal variations, the summer lower δ18 O and d-excess and winter high δ18 O and d-excess of precipitation in the southern Tibetan Plateau reflect the alternation of summer southwest monsoon moisture transport and winter westerly moisture transport. In the northern plateau, the higher δ18 O in summer and the lower δ18 O in winter are due to the fairly monotone moisture sources from the West; while the seasonal variations of d-excess in this region are resulted from the large contract of humidity conditions over the Atlantic Ocean in summer and in winter. In Altay, the north most of West China, polar air mass also affects the regional precipitation, which can also be found from the seasonal isotopic variations. The difference of moisture transports, driven by different atmospheric circulations, also affects the ice core isotopic record on the Tibetan Plateau. In the northern Tibetan Plateau, there is a consistent variation between ice core δ18 O record and local meteorological air temperature record; while in the southern Tibetan Plateau, δ18 O in ice core shows an apparent negative relation with precipitation amount in both seasonal and annual time scale.