Exposure to childhood adversity has been linked to accelerated telomere shortening, a marker of cellular aging and an indicator of physical health risk. In the current study, we examined whether adult attachment representation moderated the association between childhood adversity and telomere length. Participants included 78 young adults (M age = 20.46, SD = 1.57), who reported on their exposure to adverse childhood experiences (ACE) and were administered the Adult Attachment Interview, which was coded for attachment state of mind. Relative telomere length was assayed from buccal cells. Multiple regression analyses revealed a significant interaction between attachment state of mind and ACE in predicting telomere length. Whereas the association between number of ACE and telomere length was nonsignificant for secure–autonomous, r (50) = –.15, p = .31, and insecure–preoccupied young adults, r (9) = –.15, p = .71, there was a strong negative association between number of ACE and telomere length for insecure–dismissing young adults, r (19) = –.59, p = .007. This study is novel in demonstrating that attachment may affect biological resilience following childhood adversity, contributing to the growing literature about the role of the quality of early caregiving experiences and their representations in shaping biological processes and physical health.