OBJECTIVE Adverse childhood experiences (ACEs) of mothers may negatively affect the mental health of their offspring. Little is known about the intergenerational effect of maternal ACE on post-traumatic stress disorder (PTSD) in the offspring. This study inves-tigated the impact of maternal ACEs on PTSD in the offspring. METHODS A total of 156 mothers with children aged 13-18 years completed the Diagnostic Interview Schedule for Children (DISC) Predictive Scales to determine the presence of psychiatric disorders in their offspring. The subjects completed the ACE questionnaire and the Early Trauma Inventory Self-Report-Short Form. Multivariable logistic regression was used to analyze the relationship between ma-ternal ACEs and PTSD in the offspring. RESULTS Of the mothers, 23.7% had at least one ACE, and PTSD was reported in 21.8% of the offspring. The offspring of the mothers in the ACE group had a significantly higher rates of traumatic experiences and PTSD than the offspring of the mothers in the no ACE group. Maternal household dysfunction independently predicted offspring PTSD [odds ratio (OR)=3.008, p=0.05), and three or more maternal ACEs were significantly related to PTSD in the offspring (OR=10.613, p=0.025). CONCLUSIONS Maternal ACEs have a significant impact on the risk of traumatic experiences and PTSD in the offspring. These findings suggest the presence of intergenerational transmissions by which maternal ACEs affect the mental health of the offspring.