Abstract: According to the data of temperature and precipitation in Jinsha River analyzed by stochastic hydrology method, the annual variation and the tendency, mutation and periodicity of annual temperature and precipitation was reflected.The results show that:Firstly, the average annual temperature was below zero in upstream with interannual variation slightly, about 12℃ in downstream and between the two with smaller interannual variation in midstream.After 1980, the annual temperature increased observably, having the mutations period in 1997, 1992 and 1986, and the period of 7 to 9 years, 14 to 15 years, 23 to 25years.Secondly, the abundant annual precipitation increased gradually from upstream to downstream in main stream, well-distributed in affluent basin with smaller interannual variation.It increased indistinctively in most areas and decreased in part with the period of 2 to 3years, 7 to 8 years, and 15 years, also changing in 1997, 1992 and 1986 suddenly.