Examined the structure and correlates of a measure of prosocial moral reasoning in a sample of young and middle-aged adolescents. 1556 students (53% male, M age = 13.12, SD = .87) from Valencia, Spain completed paper-and-pencil measures of prosocial moral reasoning (PROM), empathy, prosocial behaviors, and aggression. As expected, a series of confirmatory factor and structural equation modeling analyses revealed a four-factor solution of the PROM to have the best fit (as compared to alternative models) among Spanish youth (across gender and grade). Moreover, higher level and other-oriented forms of prosocial moral reasoning were generally positively related to empathy and prosocial behaviors, and negatively related to aggression. In contrast, generally, lower level and self-focused modes of prosocial moral reasoning were negatively related to such prosocial tendencies, and positively related to aggression. Discussion focused on the psychometric properties of the PROM and its relations to theoretically-relevant correlates among Spanish youth