According to the spatio-temporal distribution characteristics of the rainfall and the geographic features,China is divided into four rainfall areas.On this basis,we developed the different assessment methods of the intensity grade of the heavy rains for every rainfall area.At the same time,elevation, standard deviation of elevation,drainage density and soil types have been identified as import controlling factors of the torrential rain disasters,and these factors were respectively classified into different grades. The comprehensive rainstorm disaster risk assessment model is established by weighted summation of the rainfall factors and the selected controlling factors.Based on the model,we further applied GIS to evaulate the number of affected urban and rural residents and land areas in different risk levels.Compared with the previous rainstorm risk assessment models,this rainstorm risk assessment model can be applied more widely in any regional rainstorm disaster risk assessment.Moreover,this model has stronger operation a-bility of pre-assessment,real-time assesment and post-assessment by using real-time or forecast rainfall data.Finally,combined with GIS,this model can achieve quantitative evaluation of the hazard-affected bodies at the different risk levels.%提文章综合考虑中国区域范围内降雨时空分布特征以及地理地貌等特征，将全国降雨区划分为4大类，在此基础上，得出不同降雨类区暴雨致灾因子的强度等级评定方法；同时，研究确定了与暴雨灾害密切相关的地形高程、高程标准差、河网密度、土壤类型等环境脆弱性影响要素，并对各类要素分别进行了分级评定；将各类环境脆弱性影响要素结合暴雨致灾因子要素，运用加权求和方法建立了暴雨灾害综合风险评估模型；并结合 GIS 技术，将城市、农村人口分布情况、用地等数据叠加到风险分布格局中，最终分析得出不同风险等级下影响的城市和农村人口数量、土地面积等内容。该评估模型相较于以往其他暴雨风险评估模型，其适用范围更广，可以适用于全国范围内的任意区域暴雨灾害风险评估；实时评估业务能力更强，将该模型结合降雨实况资料或预报资料可以对全国任意区域降雨灾害综合风险进行事后、跟踪评估或预评估；评估对象更有针对性，结合 GIS 技术，可以针对得出的风险分布结果分别给出不同风险等级范围内的承灾体受影响的定量评估结果。
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