The purpose of this study was to investigate parent perceptions of the physical activity (PA) engagement of their adult children with autism spectrum disorders. The theoretical framework used in this study was social ecology. Participants were nine parents from families with one adult child with autism spectrum disorder whose ages ranged from 18 to 42. Using phenomenological interviews, which explored parents’ life experience and meaning making, four themes were generated: supports and advocacy for PA, engaging in PA independently, benefits of PA, and barriers to or reasons for disengaging in particular activities. Parents’ interview comments showed that intrapersonal factors, interpersonal relationships, and community factors were essential for keeping the individuals with autism spectrum disorder engaged in PA. Families and practitioners can take advantage of that by seeking PA opportunities in community settings or with other individuals.