Abstract: Based on the investigation of 33 plots in Jing County and Qingyang County, the effects of site conditions on above ground biomass and bark yields, and effects of site conditions on the bark production were studied and analysed. The results indicated that:(1) Parent rock, soil texture, pH and depth of top soil were a significant influence on above ground biomass production and bark production of Pteroceltis tatarinowii plantations. Overall the highest above ground biomass production or bark production was achieved in the site condition with loam soil, where parent rock is slate, pH is less than 6.5, and depth of top soil is more than 20 cm. (2) The distribution pattern of above ground biomass components was in order of xylem>leaf>bark, and the biomass production of xylem was 6.83 times of the bark, 5.98 times of the leaf.(3) In the stand of 3 year old, the bark production could be divided into 3 parts according to the growth period. The highest bark production was achieved in the section of 3 year old, and the lowest was in the section of 1 year old. The bark production in the section of 3 year old is 1.94 times of 2 year old, 3.61 times of 1 year old. (4) The different site can divide into 3 types (A,B,C). Type A has the highest above ground biomass production or bark production than type B and type C. The rate of bark biomass to above ground biomass is 11.66% in type A, 10.95% in type B,and 10.81% in type C.