Based on the antitubercular and hypoglycemic action of coumarin derivatives, seven kinds of following derivatives of sulfonamide system were synthesized. 6-Tolylsulfonamidocoumarin (L-1), 6-(4-acetamidophenylsulfonamido) coumarin (L-2), 6-(4-aminophenylsulfonamido) coumarin (L-3), 4-methyl-6-tolylsulfonamidocoumarin (L-4), 4-methyl-(4-acetamidophenylsulfonamido) coumarin (L-5), 4-methyl-5-(4-aminophenylsulfonamido) coumarin (L-6), and 3-ethyl-6-tolylsulfonamidocoumarin (L-9). Of these compounds, hypoglycemic action of L-2 and L-3 has already been reported by Ito, et al. although its activity is not as marked as that of 2-(4-aminophenylsulfonamido)-5-isopropylthiadiazole.Antituberculosis action of these compounds were tested and reported by Mitani, and the antituberculosis action was found to be stronger when the substituent in 6-position of the coumarin ring is p-aminophenylsulfonamide group than when it is p-acetamidophenylsulfonamide group. None of the compounds synthesized were found to have stronger action than 4-methyl-7-(4-aminophenylsulfonamido) coumarin reported by Bersch, et al.