Rainfall erosivity and its characteristics were studied by analyzing rainfalls and soil erosion data recorded within the period of 1997—2003 at the ecological experiment station of red soil(EESRS),which is located in Yingtan area,Jiangxi Province.The results indicate that for the studying area,the events of rainfalls and erosive rainfalls occurred from March to August in each year.According to the method of R "EI30" value,the rainfall erosivity was 7 231.8,12 051.9,3 722.3,6 864.2,4 520.5,6 299.1 and 5 580.9 MJ·mm/(hm2·h·a) for the years from 1997 to 2003,respectively.The rainfall erosivity varied considerably not only in years,but also in months.Finally,the simple and easy algorithm for rainfall erosivity calculation was proposed based on the analysis of the relationship between the rainfall volume and sediment yield during the 244 events of erosive rainfall within the seven years.Based on the validation,the simple algorithm performed better than the traditional algorithm of EI30,particularly for the widespread purpli-udic cambosols.However,the accuracy of the simple algorithm remained almost the same as the traditional algorithm in the soils of ali-udic argosols and typic argi-udic ferrosols.The results indicate that the new simple algorithm might be suitable for wide use in the study area.