This paper studies mainly soilanti-erodibility indices of mixture-planted and pure-planted forest. Results show that soil organic material and water stable aggregate contents of mixed forest are greater than those of pure forest by 38% and 23% respectively, rate and coefficient of soil dispectively in 0-100 cm soil layers under the same condition. The difference of organic material and water stable aggregate contents between mixed and pure forest-land is extremely significant. The difference of rate and coefficient of dispersion between mixed and pure forest-land is significant, but the indices of various sooil layers is irregular.