Abstract: This paper deals with the basic characteristic of gap disturbance in a broadleaved-korean pine forest in the Changbai Mountain Natural Reserve. Some important paraments related to the disturbance regimes were described. The result shows that expanded gaps occupied 27.36% and Canopy gaps occupied 13.05% of land area in the forest. The frequency of gap disturbance was 0.15% per year. The distribution pattern of gaps in the forest belonged to the uniform type. The most important manner of gap formation was uprooting blown down, and the secondly important was breakage at trunk base. Most of gaps were formed by 1～4 gap makers. Major gap makers in the forest were Pinus koraiensis, Fraxinus mandshurica, Ouercus mongolica and Tilia amurense. The probability of making gaps was greatest when the big trees in the canopy layer got D. B. H. 40～60cm and height 25～30m.