The study employed 90 children with autism spectrum disorders (ASDs) who were matched to 90 typically developing children on age, gender, and ethnicity. Using structural equation modeling, maternal sleep and maternal stress mediated the relationship between children’s sleep and mothers’ mental health for mothers of children with and without ASDs. Mothers of children with ASDs reported more problems related to children’s sleep, their own sleep, greater stress, and poorer mental health; however, children’s sleep and maternal sleep were more closely related to maternal stress for mothers of typically developing children. Implications of these findings and future directions for research are discussed.