Abstract: The analysis results of flood disasters in recent years reveal that the extent of the disaster has great links with the topography and the distribution of river systems in Henan province. To extract the factors that affecting the distribution of flood disasters，such as topography，slope，drainage and other factors based on GIS, and weight with AHP，consequently , the map of flood disasters risk is obtained by overlay all factors using map algebra function . mean time，the map of vulnerability degree is obtained using the index of population density and GDP to analyze vulnerability degree. Ultimately，the map of flood disasters risk zoning is achieved by gird overlay analysis of the two maps, and the precision is inspected and combined with the historical flood disasters. The results show that the flood disasters risk zoning map based on ARCGIS has certain degree of accuracy，and it can provide a theoretical support for the work of the relevant departments.