Personal beliefs and attitudes about body weight and body image are important determinants of weight management practices. To inform efforts to prevent and treat obesity among autistic adults, this study examined how autistic adults perceive weight management, body weight, and body image. Eleven adults participated in semi-structured interviews. Consistent with an interpretive paradigm, an interpretative phenomenological analysis methodology was employed, resulting in four themes: (a) "Mental and physical health: direct and indirect interactions," (b) "ASD traits and health-related behaviors," (c) "Body dissatisfaction: Unrealistic ideals and misperceptions," and (d) "Sources of information." This study's findings have several implications for research and practice. First, participants viewed overweight and obesity as just one component of a holistic perspective of health. A dynamic, bidirectional relationship between mental health and physical health, including overweight/obesity was described, leading us to posit that the promotion of mental health is crucial for the promotion of overall health among autistic adults. Second, body dissatisfaction was pervasive among participants in this sample. This finding requires future research as it may be an important target for intervention, with relevance for mental health and weight management practices. Finally, interactions with medical professionals regarding weight management were perceived to be inadequate.