In order to quantitatively assess the alternation of the riverine eco-hydrological regime of the fish-protection area of the Upper Yangtze River,the daily flow data(1956 ~ 2012) at Pingshan Hydrological Station of the Lower Jinshajiang River is selected, and then the analysis of the flow characteristics therein is made with Mann-Kendall test method,accumulative departure method and slide T detected method,while both the alternation of the riverine eco-hydrological regime of the fish-protection area of the Upper Yangtze River and its impact on the riverine biodiversity are comprehensively assessed herein with the range of variability approach(RVA) for the eco-hydrological index and the hydrologic alteration degree method as well. The result shows that (1) the yearly mean flow at Pingshan Hydrological Station generally exhibits a trend of slight increase with the mutation year of 1997,which indicates that the impacts from climate change,and human activities,especially the hydropower development on the hydrology of the Upper Yangtze River are intensified; (2) the overall degree of hydrological alternation at Pingshan Hydrological Station is about 51% and belongs to the moderate alternation; in which the impacts on the flow decreasing rate and the reversion number are the most significant; (3) the hydropower development changes the eco-hydrological regime of the Upper Yangtze River to a certain extent,thus causes the decrease of the number of fish species in the Upper Yangtze River. The study result can provide reference for the riverine ecological protection and reservoir eco-operation in the Upper Yangtze River.