© 2015, Springer Science+Business Media New York. Comorbid externalizing/internalizing symptoms among children with autism spectrum disorder (ASD) often result in psychosocial distress. The current study examined how routines may be related to comorbid symptoms in children with ASD hospitalized for acute psychiatric care (n = 45) and a group of age/gender-matched typically developing peers (n = 45). Measures of routines, behavioral problems, and parental adjustment were completed by parents. Multiple regression analyses revealed a correlation between parental adjustment and internalizing symptoms among children, and a quadratic relation between routines and internalizing symptoms for the ASD group. A quadratic relation was also observed for routines and externalizing symptoms for the ASD group, whereas only parental adjustment emerged as a significant predictor of externalizing symptoms for the typically developing group. Implications for conceptualizing routines and treatment in the context of ASD are discussed.