On the basis of continuous monthly rainfall data of 21 stations in Hubei Province and 14 stations in circumference provinces, the rainfall erosivity R value is calculated by using Arnoldus simple method, and a spatialtemporal distribution analysis supported by Arcview software. The results show as follows: The spatial distribution of the R value appears increasing trend from north to south. The monthly spatial distribution of the R value is very similar to the distribution of rainfall, and the R value dynamically changes evidently among several months. The three indexes of the R value in year are characteristized by higher values in northeast region of Hubei Province and lower in southeast.