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As the link between energy balance and water cycle, changes in evaporation are of critical importance for regional hydrological cycle and water resources management of the Yangtze River basin (YZRB) . In this study, the spatio-temporal characteristics and driving mechanisms of the long- term changes in pan evaporation ( Epan ) of the YZRB from 1960 to 2019 were investigated using the PenPan model, and changes in actual evapotranspiration ( Ea ) were further evaluated using the latest generalized complementary relationship of evaporation. Results show that: ① Both Epan and Ea of the whole YZRB decreased and then increased before and after 1990. The decreases of wind speed and net radiation were the main drivers for decreasing trend of Epan before 1990, but the rise of temperature and decrease of relative humidity were the main drivers for increasing trend of Epan after 1990. ② Trends of pan evaporation in both major climatic regions of YZRB ( i. e., plateau climatic region and subtropical climatic region) were reversed before and after 1990 and were driven by different mechanisms. During 1960—1989, Epan decrease in the plateau climatic region was driven by changes in temperature and radiation, while Epan decrease in subtropical climatic region was driven by changes in wind speed and radiation. ③ During 1990—2019, Epan increase in the plateau climatic region was mainly driven by the rising temperature, increased wind speed and decreased relative humidity, while Epan increase in the subtropical climatic region was largely driven by the rising temperature and decreased relative humidity. This study can provide as a reference for the water cycle change detection and water resources allocation in the YZRB. [ABSTRACT FROM AUTHOR]