Research has demonstrated the predictive effect of maternal childhood maltreatment on adolescent internalizing problems. However, few studies have explored the mediating mechanisms of how mothers' experiences of childhood maltreatment are transmitted to their offspring's internalizing problems over time. The present multi-informant study investigated the potential mediating effects of maternal depressive symptoms and offspring's childhood maltreatment experiences on the relation between maternal childhood maltreatment and adolescent internalizing problems. A total of 823 Chinese youth (43.4% girls; Mage = 10.26 years, SD = 0.94) and their mothers participated in a two-wave longitudinal study with one-year intervals. Mothers reported their experiences of childhood maltreatment and depressive symptoms, while youth reported their childhood maltreatment experiences and internalizing problems. Findings of path analysis indicated that maternal emotional abuse at T1 could significantly predict adolescent internalizing problems at T2, after controlling for a baseline of adolescent internalizing problems. Maternal emotional abuse, emotional neglect, and physical neglect at T1 can influence adolescent internalizing problems at T2 through maternal depressive symptoms at T1 to adolescent internalizing problems at T1. Maternal emotional abuse at T1 displayed statistically significant indirect effects on adolescent internalizing problems at T2 successively through the pathway from adolescent emotional abuse at T1 to adolescent internalizing problems at T1. The findings supported the cycle of maltreatment hypothesis. The present study highlights the intergenerational link between maternal childhood maltreatment and adolescent internalizing problems, as well as reveals the mediating mechanisms in this relation.