Abstract: To define the correlation between the occurrence ofDendrolimus kikuchii and forest factors inPinus massoniana forests, an investigation recording the population density of the pest inP. massoniana forest with different forest factors was conducted by means of sampling plot survey and standard plot survey. And 13 forest factors that could influence the population distribution of the pest were analyzed using stepwise regression analysis. Results showed that 4 key forest factors were screened out, the order of importance was: aspect(x 2)＞ canopy openness(x 5) ＞ average DBH (x 13) ＞ altitudes(x 1), multiple linear regression multivariate was: y = - 1.806 - 0.196x1+ 4.574x2 - 0.320x5+ 0.232x13 .D. kikuchii insect-source site had the characteristics of sufficient sunlight, higher temperature, large diameter, and low altitude. The study can provide a reference basis for the transformation of the insect-source site ofD. kikuchii , and culturing forest with the resistance to the pest.