Moral identity research to date has largely failed to provide evidence for developmental trends in moral identity, presumably because of restrictions in the age range of studies and the use of moral identity measures that are insensitive to age-related change. The present study investigated moral identity motivation across a broad age range (14–65 years, M = 33.48; N = 252) using a modified version of the Good Self-Assessment Interview. Individuals’ moral identity motivation was coded and categorized as external, internal, or relationship-oriented. It was found that with age, external moral identity motivation decreased, whereas internal moral identity motivation increased. Effects of age were stronger in adolescence and emerging adulthood than in young adulthood and middle age. Findings underscore the developmental nature of the moral identity construct and suggest that moral motivation becomes more self-integrated with age.