Parental involvement has been associated with increased adolescent prosocial behaviors, but we know little about the peer and school-level explanatory mechanisms behind these associations. The current study aimed to examine the intervening roles of deviant peer affiliation and school connectedness in links between parental involvement and prosocial behaviors among U.S. Latino/a adolescents. Participants included 306 U.S. Latino/a adolescents ( Mage = 15.50 years, SD = .42 years, 46% girls, 81.0% U.S. Mexican) from communities in the Northern Great Plains, who reported on parental involvement, deviant peer affiliation, school connectedness, and prosocial behaviors. Path analyses showed that parental involvement was directly and indirectly related to prosocial behaviors via both deviant peer affiliation and school connectedness. Parental involvement was related to lesser deviant peer affiliation, which was in turn related to greater school connectedness, which was further related to higher prosocial behaviors. The discussion focuses on the importance of studying the interplay of parent, peer, and school factors in understanding prosocial behaviors among U.S. Latino/a youth.