Abstract: In Nanjing-Zhenjiang Hills, soil humus samples from under oaks, pine, Chinese fir,hairy bamboo forests and herb were adopted for fractionation analysis, chemical element analysis, light density measurement and infra-red spectral analysis. It turned out that soil humus in the yellow brown soil zone of northern subtiopics showed that the interim ehracters on their chemical structure, composition and properties relevant to the transitional zone of climate, but they somewhat varied on developing degree of chemical structure and quantity of groups under the influence of various vegetations. It might be accepted that the quality of soil humus under herb or bamboo stand is the best, and that under Chinese fir stand is the worst.