Abstract: Applying 53 Object tree and competitive tree’s survey data, using Hegyi individual tree competition index model, the relation of intra-specific and inter-specific competition in platycarya strobilacea and var.acuteserrata distributed in Baotianman area was quantitatively analyzed. The result shows that inter-specific competition of var.acuteserrata populations is greater than intra-specific competition, and intra-specific competition of platycarya strobilacea is less than inter-specific competition.The calculation of competition intensity from the object within the scope which on wood 2，4，6，8 m shows that the greatest competition intensity of var.acuteserrata and platycarya strobilacea appears in the 0-2 m scope，Object tree competitive strength and size of the diameter between obeying the power function of the form, and reached 20 cm diameter at breast height after the intensity of competition in the rate decreases.