While a substantial body of existing literature has examined the negative effects of parental psychological control on adolescents' prosocial behaviors, there is a noticeable gap in whether parental psychological control affects prosocial behaviors towards ethnic outgroup members. This three-wave longitudinal study investigated whether similar relations can be observed between parental psychological control and prosocial behaviors targeted at ethnic outgroup persons, and whether these relations are mediated by adolescents' intergroup attitudes. Participants were 412 European American adolescents (42% girls; Mage = 15.63 years at Time 1) and their primary caregivers (52% mothers) residing in the United States. They completed online questionnaires. Parents completed a measure of parental psychological control at Time 1. Adolescents completed measures of intergroup attitudes, public, and altruistic outgroup prosocial behavior at all three time points (T1, T2, T3), each approximately 8 months apart. The retention rate was 38.1% (N = 157; 44% girls) at Time 3. Path analyses revealed a direct negative link between parental psychological control and altruistic prosocial behavior towards ethnic outgroup persons but a direct positive association to public prosocial behavior towards outgroup persons. Importantly, parental psychological control was indirectly related to adolescents' prosocial behavior towards ethnic outgroup persons, via its effect on their intergroup attitudes. The findings underscore how parental psychological control and adolescents' intergroup attitudes contribute to shaping prosocial behaviors towards ethnic outgroups.