Abstract: Risk assessment of flash flood disasters provides a scientific basis for research on the disaster-causing mechanisms and risk zoning of flash floods.Based on GIS,geographic detectors, the analytic hierarchy process, and natural disaster risk theory, the main driving factors of flash flood disaster risk in Xinjiang Uygur Autonomous Region were identified with the support of nine index data points, such as snow water equivalent, slope and annual maximum 1-hour point rainfall.The risk assessment of flash flood disasters in Xinjiang was evaluated from three aspects: disaster-causing factors, disaster environment and vulnerability.The results show that the explanatory power of the single factor, slope, is the greatest, and the interaction between annual maximum 1-hour point rainfall and other factors exhibits nonlinear enhancement.The proportions of flash flood risk levels from high to low were 6.69%,13.63%,18.01%,25.42% and 36.25%,respectively.In general, the geological geomorphology and hydrometeorological conditions of the "Three Mountains" in Xinjiang significantly impact the formation of flash floods.Strengthening the monitoring and early warning of 1-hour short-term rainfall and snowmelt runoff is of practical significance for local resistance to flash floods.The research findings can provide a reference for the scientific assessment and prevention of flash flood disasters in Xinjiang.