Eighty-one adolescent and young mother-infant dyads have been divided into two groups with/without traumatic experiences in maternal history to examine the effect of maternal traumatic experiences on the quality of mother-infant relationship. At infant 3 months, mother-infant interaction was video-recorded. Results showed that adolescent and young mothers with traumatic experiences (vs. adolescent and young mothers without traumatic experiences) had less sensitive and more violent and intrusive behaviours. Infants with mothers with traumatic experiences (vs. infants with mothers without traumatic experiences) had more aggressive and reactive behaviours. Furthermore, maternal cumulative traumatic experiences predicted more negative behaviours. Findings indicated that maternal childhood traumatic experiences increased an adolescent mother's risk for maternal-child interaction problems, worsened the high-risk condition inherent in motherhood in adolescence. Understanding the effect of adolescent mother's traumatic experiences has important implications for promoting early intervention in the treatment of trauma and supporting the mother-child relationship.