Soil erodibility factor K of seven representative soil types in subtropical China was studied using field plots under rainfall simulator and natural rainfall respectively.The results showed that soil erodibility factor K of tilled Alfisol derived from red sandstone and Cambisol on purple shale was the highest, and of eroded Entisol derived from Quaternary red clay was the lowest. The relationships between soil erodibility factors measured by rainfall simulator and natural rainfall were also established respectively.