Inclusion of students with Autism Spectrum Disorder (ASD) in mainstream schools has a positive impact on their social and daily living behaviors. Our objective was to identify clinical and socio-demographic variables promoting or limiting inclusion in mainstream school through childhood and adolescence. The EpiTED study is a long-term, prospective, multicenter cohort of 281 ASD children included before the age of 7, with a 10-year follow-up in France. Variables significantly linked to inclusion in mainstream school were identified using a mixed-effect logistic regression model: greater autonomy [OR = 1.45 (1.29–1.63)], lesser symptom severity [OR = 0.96 (0.92–0.99)] and fewer siblings [OR = 0.86 (0.75–0.99)]. In the multivariate model, the probability for a child of being included in mainstream school decreased over time [OR = 0.91 (0.85–0.97)], i.e. with age.