In the expansion of odontogenic cyst, degradation of extracellular matrix and resorp디on of bone are accompa띠ed ， but its mechanism is under debate. The degrees of inflammation and fibrosis were graded in 39 cases of odontogenic cysts. Cytoplasrnic expressions in various cell types according to them were analyzed using immunohistochemis띠， for MMPs and πMPs. In epithelial cells, MMP-2 expression was increased with marked fibrosis(p=O.018) and in stromal cells, MMP-2,-9 and TIMP-2 expressions were slightly higher in cases with mild inflammation and marked fibrosis. Tendencies of positive correlation were found between MMP-2,-9 and TIMP-2 expressions in epithelial cells and between MMP-l and MMP-9 expressions in stromal cells. These results suggest that MMP-l ,-2 ,-9 and TIMP-2 expression might be related to the expansion of odontogenic cysts, and the expression rate of them was different according to cell types and the degree of inflammation and fibrosis.