Risk assessment of regional floods is the basis of flood disaster management. This paper takes Henan Province as the study area, where has suffered from frequent flood disasters. The main factors of flood disasters were first analyzed, and six indexes were chosen to build the assessment system of flood disaster risk from the aspects of dangerousness and vulnerability of flood disasters. The six indexes were absolute elevation, slope, average annual precipitation, river distribution, population density and the GDP density. The risk distribution map of flood disasters was obtained by using the functions of spatial analysis and overlay of ArcGIS software. Results showed that: (1) The risk of flood disaster decreased gradually from the south to north. (2) From administrative divisions, most areas of Xinyang City and some of the southern areas of Zhumadian City were in the high risk zone, Sanmenxia, Jiaozuo, Xinxiang, Hebi and Puyang Cities were in the low risk zone, and other areas were in the middle. risk zone