Abstract:In this paper, the composition,quantity, distribution of soil animals and Gilpinia lipuensis of Pinus massoniana and their relation with ecologic environment were studied. The result showed that if the canopy density of forest was big, the woodland was lack of shrub and herb, the composition and quantity of soil animals were poor and small, that the kind of soil animal was richer in middle-aged forest which had more complicated vegetation than that in young growth, and that soil animals were more at the foot of a hill than at the middle or top of it. Only one species of sawfly was found in Pinus massonianastand, that was Gilpinia lipuensis Xiao et Huang. Four species of natural enemy were found here, they were Cleptes sp. Pleolophus sp. Olesicampe sp. and Bessa selecta fugax Rondani. The parasitic rate of natural enemies accounted for 57. 5 per cent of the total emergance rate, the sawfly only made up 42. 5 percent. The quantity of empty cocoons amounted to 60. 67 percent of the total cocoons. The occurrence and degree of damage of Gilpinia lipuensis had close relations with temperature, precipitation, topography, distribution of Pinus massoniana, age of forest and structure of forest form.