Abstract: In this paper,analysis was made of the soil degradation mechanisms reasons of the Chinese fir plantation from different factors,such as irrational cultivation system and cutting method of plantation,the relase of trees allelochemicals,and so on.The results showed that (1) under three different ways of preparing soil,the fir growth increment trends wwere as follows:full reclamation > strip preparation > hole preparation,and physical and chemical indices in woodlands; (2) Different fertilization treatments had great efferts on the growth of stand.The order of the Chinese fir growth on use of different fertilization was as follows:formula fertilizer > common compound fertilizer > control treatment; (3) Biomass of organs increased in number with the prolonging of rotation,among which the accumulation in trunk was the most and fewer in branch leaves.Chinese fir plantation soil degradation mechanisms were found by utilizing the researches on the growth of Chinese fir plantation,nutrient balance and the basic theory and relative technologies of soil productivity maintenance.At the same time,the targeted soil productivity maintenance technique was also put forward.