High rates of depressive disorders are reported among young people on the autism spectrum. This condition is generally assessed using measures validated for typically developing young people. Tools adapted to children on the autism spectrum are not tailored to detect Major Depressive Disorder, nor have they been used among samples with an intellectual disability. To fill this gap, this article builds a novel "Scale for evaluating depressive symptoms among youth on the autism spectrum" ("Echelle d'évaluation de la symptomatology dépressive spécifique à l'autisme") and evaluates its performance using a sample of 153 young people on the autism spectrum in France. The "Echelle d'évaluation de la symptomatology dépressive spécifique à l'autisme" was completed by parents of children and adolescents (aged 3-17 years) via an interview with a psychologist. The "Echelle d'évaluation de la symptomatology dépressive spécifique à l'autisme" has very good internal consistency, as well as good content validity. The scale is composed of two factors: (1) behavioral changes and (2) emotional and cognitive changes. Future studies should replicate this validation study with a larger sample size and investigate interrater reliability. Overall, results suggest preliminary support for using the "Echelle d'évaluation de la symptomatology dépressive spécifique à l'autisme" among youth on the autism spectrum.