This study proposes a revision (R) of the Center for Epidemiologic Studies Depression Scale for youth with ID (CESD-ID) in English and French. 346 youth (36.02% girls) with mild (51.26%) and moderate (48.78%) ID (11-22 years; M = 15.69), enrolled in secondary schools in Canada (French-speaking; n = 115), and Australia (English-speaking; n = 231), as well as their parents and teachers, participated in this study. Results support the reliability, factor validity, equivalence (sex, ID level, comorbidities, and country), and convergent validity (with youth-, parent-, and teacher-rated measures of depression, anxiety, and loneliness/social isolation) of the CESD-ID-R. The CESD-ID-R allows youth with ID to provide a reliable and valid assessment of their depressive mood and happiness suitable for epidemiological studies.