Abstract: Flash flood disaster prone to strong，fast disaster，serious harm，difficult to defense，and it became the focus and difficulty of flood prevention work.Taking Zhongning county of Ningxia autonomous region as a unit，investigation and evaluation of flash flood disaster were carried out.Basic informations of villages and towns in prevention and control area were investigated.Evaluation object directory was determined.Corresponding rainfall warning indicators were determined through analysis of designing storm flood calculation，evaluation of current situation of flood control capacity and classification of hazardous area.It provided basic data and technical support for flood control department in command and decision making and engineering management.