ImportanceIt is widely known that individuals with adverse childhood experiences (ACEs) have an increased risk of abusing their own children, thereby perpetuating the cycle of violence. However, the association between ACEs and elder abuse perpetration has not been fully examined.ObjectiveTo examine the association between ACEs and elder abuse and the mediating factors.Design, Setting, and ParticipantsThis cross-sectional study used data collected via the self-administered Japan COVID-19 and Society Internet Survey from September 12 to October 19, 2022. Men and women aged 20 to 64 years who responded to related questions were included. Data were analyzed from July 2023 to April 2024.ExposuresACEs, defined as the experience of any of 7 items—interpersonal loss (parental loss and parental divorce), family psychopathology (parental mental disease and violence in family), abuse (physical and psychological abuse), and neglect—before the age of 18 years.Main Outcomes and MeasuresThe primary outcome was the perpetration of physical and/or psychological abuse against an older person (aged ≥65 years) self-reported via questionnaire. The direct and indirect effect estimates were determined using logistic regression analyses.ResultsOf a total of 13 318 participants (mean [SD] age, 41.1 [12.1] years; 6634 female [49.8%]), 1133 (8.5%) reported perpetrating violence against older adults. Compared with individuals without ACEs, the odds ratios (ORs) for perpetrating violence were 3.22 (95% CI, 2.74-3.79) for those with 1 ACE and 7.65 (95% CI, 6.41-9.13) for those with 2 or more ACEs. In the mediation analysis, factors with large indirect effect estimates included depression (OR, 1.13; 95% CI, 1.11-1.14; proportion mediated [PM], 18.6%), mental illness other than depression (OR, 1.12; 95% CI, 1.10-1.14; PM, 17.3%), and self-rated health (OR, 1.04; 95% CI, 1.03-1.05; PM, 6.0%).Conclusions and RelevanceThese findings suggest that intergenerational cycles of violence may extend to any vulnerable group, not only children but also older adults. Further research into the prevention of ACEs and breaking these cycles of violence is warranted.