Abstract: In order to comprehensively grasp the water ecological change state of Dongting Lake and provide theoretical support for improving its ecological environment, we collected and sorted out the water quality monitoring data of 11 monitoring sections in Dongting Lake from 1989 to 2018,and analyzed the water quality evolution characteristics and trophication status of Dongting Lake by single factor evaluation method and comprehensive nutritional status index.In addition, we screened and identified the socio-economic and hydrological driving factors, analyzed the driving factors by stages using principal component analysis method and multiple regression analysis method, and put forward several strategies for water environment protection in the lake area.The results showed that:(1) from 1989 to 2018,the water quality of Dongting Lake dropped significantly and was in a state of mild eutrophication; from the perspective of spatial evolution, the distribution of eutrophication was as follows: East Dongting Lake > South Dongting Lake > West Dongting Lake.TN and TP were the key influencing factors; through identification and screening, socio-economic development and hydrological status were the two driving factors.(2) From 1989 to 2002,the overall water quality in Dongting Lake showed a significant downward trend too, with socio-economic driving factors being the key factors; from 2003 to 2007,the water quality in Dongting Lake changed relatively steadily; from 2008 to 2018,the water quality decreased obviously in the early stage, which was affected by two driving factors of socio-economic development and hydrological change, however in the later stage, due to the increased efforts in water pollution prevention and control, the water quality was gradually improved.(3) According to the analysis results of water quality evolution in Dongting Lake, in order to improve it's ecological environment, it is suggested to strengthen the control of domestic pollution, prevent and control industrial point source pollution, strictly control agricultural non-point source pollution and strengthen the regulation of water resources in Dongting Lake.