Parents of children with ASD who had attended an Australian emergency department (ED; n = 421) completed a questionnaire relating to their experiences in the ED, including (1) child's reason for presentation and existing comorbidities, (2) quality of care during the visit (3) child's behaviour during visit, e.g. sensory responses to the ED environment, and disruptive behaviours. Children with comorbid ASD and intellectual disability were more likely to present with gastrointestinal issues and seizures, while those with comorbid ASD and oppositional defiant disorder were more likely to present with self-injury. ED staff awareness of ASD-related issues, including communication and expression of pain, were common difficulties for parents. The ED environment (e.g. lights, sounds, waiting areas), exacerbated child anxiety and led to disruptive behaviour.