In this research rainfall data studied in the forms of erosivity equations for the reason of determining

vulnerable areas affecting by rainfall erosivity in Ardabil Province, Iran. Initially the rainfall data from 71

stations into and around of Ardabil Province collected and analysed as amounts, intensities and other

related parameters for erosivity. Therefore the rainfall erosivity maps in different forms supplied and

classified in ArcGIS9.3 using GIS and geostatistics common capabilities. The evaluation of different

rainfall erosivity methods by the amounts of 11 distributed catchments specific sediment yields showed

that the I60 index (the maximum rainfall intensity in one hour) is the best for explaining the rainfall

erosivity in Ardabil Province.