An object of the present invention is to provide a novel benzazepine compound or a salt thereof, which has excellent vasopressin antagonistic activity. The benzazepine compound or a salt thereof of the present invention is represented by Formula (1): wherein R 1 , R 2 and R 5 may be the same or different and each represents H or D； and R 3 and R 4 each represents a C 1-6 alkyl group, a C 1-6 deuteroalkyl group, or a C 1-6 perdeuteroalkyl group.
