Based on the comprehensive investigation of the mountain torrential disaster in the city of Ganzhou，this paper uses the hydrological method to analyze and evaluate the characteristics of the storm flood，the current status of the flood control capacity，and the early-warning indicators in the key prevention and control areas，and obtains the status and characteristics of the torrential disaster in the city of Ganzhou.Defensive countermeasures are available for decision making on flood prevention and disaster reduction.