The present study examined influences of sixth-grade student-reported parent educational involvement on early adolescent peer group affiliations at seventh and eighth grade. In addition, student gender and ethnicity were explored as possible moderators. Drawn from a large effectiveness trial, participants in this study were 5,802 early adolescents across 20 middle schools in the northwest region of the United States. Findings suggested that specifically parent's educational involvement in sixth grade predicted increases in positive peer affiliation, when controlling for a general score of parent monitoring practices. The relation between parent educational involvement and peer affiliation varied by student ethnicity but not by gender. Findings suggest the social benefits of parent's engagement with the school context on early adolescent development.