Doulas, whose traditional role is to support women during labor and delivery, are being increasingly utilized within community‐based programs where a primary goal is supporting mother–infant relationships. The present study investigated the effect of doula services on parenting among young, low‐income mothers. A total of 248 pregnant women were randomly assigned to receive either doula services or routine medical and social services. The doulas provided prenatal home visitation, support during labor and delivery, and 3 months of postpartum home visitation. Parenting was assessed through video recordings of mother–infant interaction at 4, 12, and 24 months of child age and maternal report of parenting attitudes and stress. Intent‐to‐treat analyses showed that mothers who had received doula services endorsed more child‐centered parenting values, showed more positive engagement with their infants, and were more likely to respond to infant distress at 4 months. Their infants were less likely to show visible upset during observed interactions. Most effects of the program on parent and child behavior faded over time. Community doula intervention is a promising practice for supporting parenting and parent–infant interaction. Integration of doulas into longer term home‐visiting models might sustain the early impact of doula services and enhance parenting services offered by traditional home‐visiting programs.