Abstract: Spatial patterns of main species and of different various age classes of Koreanpines in the Korean-pines broadleaved forest in Changbai mountain were studied using pattern simulation analysis method based on coordinate data sets. The results are as follows: (1) Spatial pattern of Korean-pine changed in different forest types and developmental stages. Adult Korean-pines distributed randomly but the aggregation is stronger in Pinus koraiensis- Picea jezoensis-Abies nephrolepis forest. (2) Patterns of Korean-pine changed from aggregation to randomness and random self-thinning is an important factor of the dynamics.