Children with autism spectrum disorders (ASD) are twice as likely to die from unintentional drowning compared to same-age children without ASD emphasizing the importance of water-safety skills and knowledge. Yet little research has been published on perceptions of water safety for this population. The objective of the study was to investigate parental perceptions of water safety amongst children with ASD. An online questionnaire focusing on parental perceptions of water safety was distributed to parents of children with ASD associated with autism support groups across Canada. Forty-nine parents completed the self-report questionnaire with items related to demographics, swimming proficiency and lessons, adult supervision, and emergency safety procedures. Most parents (70%) believed that swimming ability was more important than supervision in ensuring water safety amongst children with ASD. Results highlighted discrepancies between reported and actual knowledge of emergency resuscitation procedures amongst parents of children with ASD. Parents of children with ASD may underestimate the importance of supervision and overestimate the role of swimming proficiency in ensuring the safety of children with ASD in aquatic environments. Future studies may benefit from exploring ways to promote effective strategies for encouraging water safety in this population.