Abstract: In order to study the effects of different stand types of Mongolian scots pine (Pinus sylvestris var. mongolica) on the diversity of insect community in the plantation under close-to-nature forest management, the structure of the insect community was studied in five stand types of the Mongolian scots pine pure forest and mixed forests in Saihanba Nature Reserve. The insects were collected by the sweep net method, and the diversity index, similarity, principal component, and stability of insect communities in different forest types were analyzed. In total, 9617 insects, belonging to 7 orders, 70 families, 195 species, were collected, and the Diptera, Hemipteran and Coleopteran were the dominant groups. The insect species in 5 stand types were all rich, and the insect community structure among the different stands reached a moderate dissimilar level. The species and individual number of mixed forest was more than those of pure forest. There was no significant difference among different stand types in insect community character indices. Principal component analysis indicated that phytophagous group, predatory group and parasitic group in each stand type were the main factors influencing the community structure, and predatory group and parasitic group had a stronger control effect on phytophagous group. The structure of insect community in the diffe-rent forest stand types had relatively high stability.