To know the in vitro and the in vivo cytotoicity of resin solution, resin solution was applied to cultured fibroblast and was injected into the mouse. The cytotoxic effect of resin solution was measured by MIT assay and in vivo cytotoxicity was examined after Hematoxylin and Eosin staining. The cell activity of resin solution in the concentration of 50% was significantly decreased compared to control group and 5 % group. In histopathologic study of resin solution, there were severe inflammatory cell infiltration, mild interstitial edema, trace hemorrhage, and moderate or severe muscle destruction in resin injected group. These results suggested that there might be some differences between the cell viability of fibroblast and in vivo cell cytotoxicity. Further study is needed to clarify the cytotoxicity by direct implanting of resin mass.