Autistic youth experience high rates of maltreatment. Little research has considered how distinct abuse dimensions differentially relate to meaningful outcomes, nor taken an intergenerational approach to consider how caregiver trauma and child maltreatment are related. This study sought to identify how parent-reported child abuse subtypes and parent posttraumatic stress disorder (PTSD) relate to each other and to admission characteristics upon inpatient service entry. Autistic youth (N = 527; 79% White, 21.3% girls, mean age = 12.94 years) participated in the autism inpatient collection. Parents reported on child abuse subtypes (physical, sexual, emotional) and their own PTSD, child behavior and emergency services, and parenting stress. Youth of parents with PTSD were nearly three times more likely to have parent-reported physical and emotional abuse. Autistic girls were more likely to experience parent-reported sexual abuse and a higher number of subtypes. Lower income related to higher rates of parent-reported child emotional abuse and parent PTSD. Emotional abuse associated with child behavior whereas both child physical and emotional abuse related to emergency services. Reported parent PTSD associated with child behavior and parental distress. When considered jointly, parent PTSD and number of parent-reported child abuse subtypes differentially related to child behavior and interacted to predict psychiatric hospitalizations. Intergenerational continuity of trauma is important to consider among autistic youth, and both parent-reported child abuse and parent PTSD relate to admission characteristics. Critical limitations include reliance on binary parent reports of child abuse and parent PTSD and the low representation of youth of minoritized identities. Implications for trauma-informed care are discussed.