Precipitation plays an important role in exerting the water conservation function and maintaining the ecology in the source region of the Yangtze River. Based on the two different kinds of dataset including gauged point data and reanalysis distribute data in 1966~2017, the spatiotemporal distribution of the precipitation changes was analyzed by the linear regression, moving average, Mann-Kendall test, box plot method, and correlation test, etc. The results show that the annual precipitation in the source area presented a steady and slow increasing tendency in terms of time distribution; furthermore, at the 0.05 test level, the tendency became significant in 2009 which was 2.3 times the average annual increase. The trend of uneven distribution of precipitation during the year had increased that after the mutation point in 2002, the probabilities of the month with extreme precipitation increased to triple, and the proportion from June to September was increased by 11%. In terms of spatial distribution, the precipitation in the source area was small, and the changing trend was basically consistent with the average surface precipitation; while the precipitation of downstream outlet was abundant, meanwhile, the same features were expressed in the frequency of extreme precipitation months, and each site shows an unstable trend of change. Under the global climate change, the precipitation in the source region of the Yangtze river has great heterogeneity in the spatial and temporal distribution, and the increase of precipitation was mainly concentrated in the flood season of the downstream export area, which may make the water ecology in the source area face more adverse environment.
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