Based on the observation data from 125 stations in Yunnan Province, the reanalysis data from National Centers for Environmental Prediction/National Center for Atmospheric Research and the monthly extended reconstructed sea surface temperature data from the National Oceanic and Atmospheric Administration in 1960-2013, the variation of the Yunnan rainfall and its related atmospheric circulation were analyzed. Major results are as follows: Yunnan rainfall experienced an abrupt decrease in 2002, which is mainly attributed to the notable reduction of Yunnan summer rainfall. Further analyses verified that the prominent decrease in Yunnan summer rainfall seems to be related to the intensified easterly of lower troposphere and strengthened westerly of upper troposphere over tropical Indian Ocean. Besides, the increasing temperature of the Asia continent in middle and high latitudes also play an important role in the abrupt decrease of Yunnan summer rainfall.