Novel indansulfamide derivatives or a pharmaceutically acceptable salt thereof such as N-[(1S)-2,2,5,7-tetrafluoro-2,3-dihydro-1H-inden-1-yl]sulfamide, N-[(1S)-2,2,4,7-tetrafluoro-2,3-dihydro-1H-inden-1-yl]sulfamide, (+)-N-(2,2,4,6,7-pentafluoro-2,3-dihydro-1H-inden-1-yl)sulfamide, have an action of improving Seizure Severity Index (Score) in mice kindling model. Thus the compounds or the salt thereof are expected as a drug for treating epilepsy.
