The present study sampled a racially diverse group of 207 women at five time points from the third trimester of pregnancy until one year postpartum. Group-based developmental trajectory modeling was used to examine unique trajectories of women’s depressive symptoms (CES-D) across the perinatal period. Analyses yielded four distinct depression trajectory groups, conceptualized as the low symptom group, the intermediate symptom group, the desist-return group, and the chronic depression group. Next, fathers’ roles were examined as predictors of maternal depression trajectories in resident- and non-resident father families. Specifically, aspects of father involvement were assessed as predictors of women’s membership to depression trajectory groups, both in the full sample of women, and in separate models that examined unique components of father involvement in resident- and non-resident father families. Mothers’ relationship satisfaction was also assessed as a predictor of trajectory group membership. Contrary to the author’s expectations, family structure did not moderate the relation between either father involvement or mothers’ relationship satisfaction and mothers’ membership to depression trajectory groups. Instead, unique sets of predictors provided the best solution for predicting mothers’ trajectory group membership based on family structure. Among women in resident father families, low coparenting conflict was the best predictor of membership to the low symptom trajectory group. For women in non-resident father families, feeling more satisfied in their relationship with the baby’s father predicted membership to the low symptom group. These findings highlight specific ways in which fathers can enhance women’s mental health during a sensitive period. Implications for providers are discussed.