Abstract: A quantitative method for assessment of regional heavy rainfall intensity is proposed, cases of Fujian Province are taken as examples. Based on the daily precipitation dataset of 66 stations in Fujian from 1961 to 2010, a definition of the regional heavy rainfall is first determined. Then four indices including maximum daily precipitation and maximum accumulated precipitation during the process are constructed as factors to evaluate an objective assessment model of composite intensity of regional rainfall.Using statistical methods such as percentile, the grade-level standards for the four indicating factors are studied. Finally, an assessment model of composite intensity of regional rainstorm is built. Compared with historical cases, the assessment model is reasonable and consistent with historical extreme cases.