Abstract: Research on evolution and related driving mechanism of flood disasters is the basis for scientifically planning flood control and disaster mitigation measures.Linear regression and the Mann-Kendall test were used to analyze the evolution law of flood disaster losses in Guizhou Province from 1979 to 2020,and correlation and qualitative analysis of the driving forces were also conducted to explore the driving mechanism of disaster changes from the risk of flood disaster-causing factors, economic and social exposure and the response ability of disaster carriers.The results showed flood disaster losses in Guizhou Province were still serious in the past 10 years(2010s),with the direct economic losses of 5.05 billion yuan per year and the mortality of 48 people per year.From 1978 to 2020,the direct economic losses caused by the flood and waterlogging disasters were increasing significantly, while the mortality reduced significantly.Although heavy precipitation increased the flood hazards, the increase of direct economic losses were mainly driven by the increase of the exposure of economic assets during the recent decades.Implementation of flood engineering and non-engineering measures in recent decades have played an important role in reducing flood disaster losses, especially in reducing flood risk, reducing economic and social exposure, and improving the emergency response ability of related local governments and people threatened by floods, but they still lag behind demand of economic and social development.The research results can provide a scientific basis and strong support for further strengthening the flood disaster control and risk management in Guizhou Province.