Abstract: Based on the field data collection, aggregation indices and regressive analysis method, the spatial distribution pattern of Tomicus brevipilosus adult in treetops of Ninger County Puer city was tested, and then the occurrence and spatial distribution pattern were analyzed further by SPSS. The results showed that, among 6 environmental factors, slope position, trees growth and age had not been introduced to equation. It suggested that the key environmental factors affecting the Tomicus brevipilosus population density were slope direction,‘victim’ treetops′ diameter and canopy, and slope position, while tree growth and age had not significant effect on density. The results of analysis indicated that, in Pinus kesiya var. langbianensis forest of Ninger County, the spatial distribution patterns of Tomicus brevipilosus adult in treetops was aggregated distribution, and the causes of the phenomenon were believed to be both characteristic itself and environment heterogeneity.