Potential evapotranspiration (PET) is crucial to water resources assessment and climate change. Based on the Penman-Monteith equation proposed by Food and Agriculture Organization (FAO) and daily meteorological data of 90 meteorological stations in Southwestern China, daily potential evapotranspiration at 90 meteorological stations was calculated. Then, various statistical methods were used to analyze its spatial and temporal variations. The results showed that the mean annual potential evapotranspiration in the whole Southwestern China during the recent 52 years was 3 209.8 mm, the highest potential evapotranspiration value was observed in Yunnan Province (3 664.7 mm), followed by Sichuan Province (3 015.0 mm), Guizhou Province (2 958.0 mm), and Chongqing Municipality (2 972.4 mm). PET in summer was the highest, followed by spring, autumn and winter. Distribution characteristics of four seasons are different from that of annual mean. Moreover, the linear changing trend of potential evapotranspiration in Southwestern China was 0.9 mm/10a. There are 31 stations showing a decreasing trend (p<0.1) and 17 stations showing an increasing trend (p<0.1). Decreasing PET in spring and summer was found at 55.6% and 63.3% of all stations, respectively. While increasing PET in autumn and winter was found at 62.2% and 58.9% of all stations, respectively. Through the abrupt change test and moving t-test, a significant abrupt point was found in 1995 for PET of Southwestern China (p<0.05). Among the 90 stations, abrupt points of 76 stations concentrated in the 1980s. In additional, 15 stations had no abrupt points which mainly distributed in the eastern margin of the Tibetan Plateau. On the whole, PET in Southwestern China increased slightly from 1962 to 2013. However, some regions appeared an opposite trend. The abrupt test also showed the same pattern. Complex terrain environment and climate characteristics are the main factors reflecting the unique feature of hydrometeorology changes in Southwestern China.