The present study was designed to examine the direct and indirect relations between acculturative stress and Latinx youth prosocial tendencies. In addition, we considered family conflict, parental support, and parental psychological control as explanatory mechanisms. Participants included 306 (53.8% female, M age = 15.50, SD = .42; range = 14 to 18) Latinx adolescents and their parents (87.9% mothers). The majority of adolescents were born in the U.S. ( n = 206, 68.0%; average time in U.S. = 10 years) and identified as a Mexican heritage group member ( n = 248, 81.0%). Findings differed by youth gender and suggest that for boys, parental support (but not psychological control) serves as underlying mechanism in the effects of acculturative stress and family conflict on youth's prosocial behaviors. Contrastingly, for girls, parental support (but not psychological control) serves as underlying mechanism in the negative effects of family conflict (but not acculturative stress) on youth's prosocial behaviors. The findings are discussed in the context of the need for integrative theories that account for cultural, family and gender-related socialization mechanisms to better understand prosocial behaviors among Latinx youth.