Autistic adults experience a higher rate of physical and mental health conditions and lower rates of employment and post-secondary education participation than their non-autistic counterparts, which may affect negatively quality of life. Limited information exists on predictors of quality of life for autistic individuals, or how quality of life compares to non-autistic individuals. Our aims were to (a) examine and compare indicators of physical (e.g. sleep quality) and mental health (e.g. anxiety) on quality of life among a sample of 244 autistic and 165 non-autistic individuals aged 15-80 years and (b) examine factors contributing to quality of life 2 years later among the autistic sample (n=93). Participants were from two Australian longitudinal studies. The pattern of results for quality of life was similar across the autistic and non-autistic groups, with depression symptomatology, psychological well-being, sleep quality and autonomic symptoms all significantly predicting quality of life. In addition, among the autistic group, baseline quality of life had the greatest influence on quality of life 2 years later. These findings have implications for support services for autistic individuals, implying that in order to improve quality of life, mental health, particularly depression, needs addressing. Given known relationships between sleep and mental health, an intervention addressing these may have greatest clinical impact on quality of life among autistic individuals.