On the basis of analysing the soil and water conservation mechanism of level terrace, the classification, the soil and water conservation benefit of level terrace with different quality, and the effect on resistance to storm of level terrace by its work quality were studied. The results showed that the soil and water conservation benefit of level terrace is difficult to reach thoroughly because of that work quality; level terrace with different quality has different soil and water conservation benefit, the bigger the rainfall amount, the more discrepant the soil and water conservation benefit of different quality level terrace; in the extreme storm, the destroy of level terrace is as a result of unqualified work quality. Above all, the work quality of level terrace plays an important role in soil and water conservation.