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Precipitation mean and extremes and their potential future changes in the Middle and Low Yangtze River Basin (MLYRB) were assessed using the models of the fifth phase of the Coupled Model Intereomparison Project (CMIP5).First, historical model simulations were compared with observations in order to evaluate model performance.In general, the models simulate the precipitation mean and frequency better than the precipitation intensity and extremes, but still have difficulties capturing precipitation pattern over complex terrains.They tend to overestimate mean precipitations while underestimate the extremes.After correcting model biases, the multi-model ensemble mean was used to project changes for the years 2021-2050 and 2071-2100 relative to 1971-2000 under two emission seenarios: RCP 4.5 and RCP 8.5.Results show that with global warming, precipitation will become less frequent but more intense over the MLYRB.Relative changes in extremes generally exceed those in mean precipitation.Moreover, increased precipitation extremes are also expected where mean precipitation is projected to decrease under the RCP4.5 scenario by the end of 21st century.This result suggests that extreme events are likely to be more sensitive to global climate change, which could lead to more frequent future floods in this already flood prone region.