This study examined the extent to which adolescents are at increased risk for postpartum depression. Mothers, ranging in age from 15-37, comprised two samples: 77 adolescent mothers (15-20 years) and 151 adult mothers (21-37 years). Six weeks postpartum, 61% of the adolescent mothers and 37.7% of the adult mothers met Beck Depression Inventory criteria for mildly to severely depression. Adolescent mothers reported significantly higher perceived stress and postpartum depression, but lower social support and self-esteem than adult mothers. Among 21 symptoms of depression, adolescent mothers exhibited significantly higher cognitive-affective symptoms than adult mothers. Adolescent mothers reported higher levels of somatic symptoms than adult mothers, but did not reach statistical significance. Low self-esteem was the significant risk factor of postpartum depression for adolescent mothers. In addition to low self-esteem, high stress was significant risk factor of postpartum depression for adult mothers.