In a country, where rainfall can reach dimensions up to 10000 mm/year, water erosion is a very important task. This study aims to evaluate the spatial distribution of rainfall erosivity over the last decades and to produce a map of average annual rainfall erosivity for New Zealand. Rainfall erosivity is reviewed almost all over the world, but only a few scientists have used the (Revised) Universal Soil Loss equation to evaluate the state of the art in New Zealand. It is known, that the R-factor is one of the major key elements within this equation. Therefore, to evaluate R-factor values for New Zealand, gauging stations with a good spatial distribution all over the country were chosen. The main aspect of this thesis is to determine R-factor values for its different climatic regions within the country, in order to create a rainfall erosivity map. Therefore, the relationship, R = aPb between the annual precipitation (mm) and the annual rainfall erosivity rate (MJ.mm.ha-1.h-1) has been determined. With this relation, the empirical parameters a and b could be identified by transforming the linear equation into a power equation. With this attempt, the erosivity rate for gauging all over New Zealand could be roughly estimated. An important point in this study was, that the empirical parameters were edited for different climatic regions within the country. Even though the parameters were adapted, a 100% accurate reflectance is almost impossible with this amount of data. Next to the 29 analysed stations, the mean annual rainfall from 218 stations was calculated and the annual erosivity rate predicted. With the analysed data, an annual rainfall and an annual rainfall erosivity map was created in GIS, to compare the spatial distribution of the annual rainfall depth and the annual rainfall erosivity.