This paper is based on the survey data of 24 sample-plots in Pinus massoniana plantaion in the mountain area of Gaozhou county, West Guangdong province. The main factors affecting the productivity of P. massoniana plantation,selected by stepwise regression analysis, are slope position, slope shape and aspect. The effect of slope position is the most significant among them. The sequence of productivities of P. massoninana plantation which on different slope positions in the same mountain area is as following, low/middle>middle>middle/above >above, the difference of which is significant or very significant.