Early maternal sensitivity to child distress is predictive of child subsequent social-emotional adjustment. A mother’s global parenting self-efficacy shapes her adaptive responses to child challenging behaviors (e.g., negative emotions). However, little is known about the antecedents of maternal self-efficacy in managing child distress. Using longitudinal data from a diverse sample of 259 primiparous mothers and their toddlers, we tested a model predicting maternal self-efficacy in managing toddler distress. Mothers’ remembered childhood experiences of maternal nonsupportive emotional socialization were positively associated with their self-reports of attachment avoidance and anxiety. Furthermore, a negative link between mothers’ self-reports of attachment avoidance and their self-efficacy in managing toddler distress was identified when toddlers displayed higher negative affect. Most importantly, a conditional indirect pathway was found. That is, only when toddlers displayed higher negative affect, mothers’ remembered early experiences of maternal nonsupportive emotional socialization were negatively associated with their self-efficacy in managing toddler distress through a positive association with their self-reports of attachment avoidance. Although maternal attachment assessed with Adult Attachment Interview was also included in analyses as a parallel mediator to self-reported attachment, no relevant effects emerged. These results suggest that by disrupting attachment development, parents’ early emotion socialization experiences hold long-standing implications for their subsequent confidence in managing child distress. Child distress as a threatening, attachment-related stimulus may contextualize such effects via interfering with the operation of caregiving system, especially for avoidant parents. Such findings may inform the designs of more targeted interventions to assist first-time mothers in navigating emotionally evocative challenges during toddlerhood