Abstract: A number of major indices including vegetation layering, species richness, individual number of each species, biodiversity, evenness, ecological dominance, and the importance value of different species in both of the pure and mixed stands of Pinus massoniana and Pinus thunbergii were investigated and analyzed.It was showed by the results that the species richness and the plant diversity increased greatly in both of the pure and mixed stands of Pinus massoniana located in inner continental habitats after having been invaded by Bursaphelenchus xylophilus disease, instead of degenerating to shrub community.The biodiversity index, species richness, and individual number were greater in the mixed stands than those of in the pure stands of Pinus thunbergii after having been invaded by Bursaphelenchus xylophilus disease.The species richness and the biodiversity of the arbor storey in both of the pure and the mixed stands of Pinus massoniana were higher than those of in the stands of Pinus thunbergii, and the composition and spatial distribution of Pinus massonianas stands became more rational after having been invaded.