This study drew on the biological sensitivity to context model (Ellis & Boyce, 2008) and polyvagal theory (Porges, 2007) to evaluate the moderating influence of children's autonomic nervous system (ANS) regulation on pathways from child emotional abuse (CEA) and child physical abuse (CPA) to later dissociative symptoms in adolescence. Participants were 232 youth (50.2% assigned female at birth, 45.9% Latine) who reported on their experiences of CEA and CPA at ages 6, 8, and 10 years. Resting cardiography measures of respiratory sinus arrythmia (RSA) and pre-ejection period (PEP) assessed children's parasympathetic and sympathetic activation, respectively, at these same ages. Youth reported on their dissociative symptoms at age 17. Parasympathetic activation qualified predictions from CEA to dissociative symptoms with relatively high RSA sensitizing children to CEA effects. Sympathetic activation qualified interactive predictions from both CEA and CPA to dissociative symptoms, but in different directions depending on the level of CPA. These findings suggest that resting ANS regulation may sensitize children to the effects of CEA and/or CPA on later dissociative symptoms in adolescence.