AbstractAn 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): Rewherein RI, R2 and R5 may be the same or different and each represents H or D and R5 and R4 each represents a C1-6 alkyl group, 10 a C16 deuteroalkyl group, or a 01-6 perdeuteroa1kyl group.