In the infant mental health field, scant conceptual attention has been given to coparenting and family adaptations of non-white family systems, with no evidence-based, community-informed coparenting interventions responsive to unmarried Black mothers’ and fathers’ life circumstances. This study examined 1-year post-partum child and family outcomes of a novel, modest dosage (six sessions) prenatal focused coparenting consultation (FCC) using randomized controlled trial methodology. One-hundred-thirty-eight expectant families (one or both parents identified as Black/African American) were randomized to an intervention (N = 70) or treatment-as-usual (TAU; control) condition (N = 68). TAU families received navigational support in accessing existing community services for pregnant families. Intervention families received TAU plus 6 dyadic FCC sessions led by a Black male-female Community Mentor team. When infants were three and 12 months old, parents reported on coparenting, father engagement, interparental aggression, depressive symptoms, and infant social and emotional adjustment. Intent-to-treat analyses focusing on 12-month post-partum data indicated significant intervention effects on coparenting, interparental psychological aggression, and infants’ emotional adjustment. Improvement was also seen in depression and father engagement, with gains for both groups. Results suggest FCC delivered by same-race Community Mentors to unmarried Black coparents transitioning to parenthood supports infant and family adaptation during the first year of life.