The activities of poyphenol oxidase, peroxidase, acid phosphatase and trypsin were measured in the presence of four different water miscible solvents, acetonitrile; N,N, dimethylformamide; tetrahydrofuran and dioxane. Stimulation of enzymatic activities was observed in all the cases at a specific concentration range of cosolvent added which cannot be correlated either with log P or denaturation capacity. Also, no significant structural changes were observed by fluorescence studies even at the cosolvent concentrations where activity increases were significant.