Based on analysis of the pluviometric data of 408 rainfall events in 8 years at Lanxi and Shengzhou Soil and Water Conservation Experiment Stations in Zhejiang Province, 3 factors, i.e. monthly erosive rainfall (P_mer), number of days of erosive rainfall in a month (D_mer), and maximum 3-day rainfall in a month (Z_3m ), were proposed, and a computation method defined, And both were introduced into the monthly rainfall erosivity models. The method of excluding low intensity rainfall, using of P_mer/ D_mer to indirectly reflect I′factor in the model, and building of composite indexes, have a good effect on establishment of rainfall models. Results show that relative deviation of the new models based on P_mer, D_mer, Z_3m is only 9.9%, while that of the traditional single rainfall factor models is 21.6%. Obviously the former is better than the latter.