Abstract： In order to well understand the effect of soil enzyme activity on soil organic matters, the relationship between soil organic matters and soil enzyme activity of the Davidia involucrate virgin forest on Mt. Baiyun in Mianzhu, Sichuan, China was studied through path analysis. The results showed that urease activity with the maximum of path coefficient and determinative coefficient was the main factor of five soil enzymes affecting soil organic matters. Catalase, acid phosphatase and protease possessing significant correlation with soil organic matters were mainly the indirect factors affecting through urease activity. So the soil urease activity of the D. Involucrate virgin forest could characterize the content status of organic matters and be used as an important index of soil fertility.