Identifying and measuring anxiety in young people on the autism spectrum can be challenging. The present study investigated the use of the Anxiety Scale for Children with Autism Spectrum Disorder (ASC-ASD), a self- and caregiver-rated screening tool in a Singaporean sample of ninety-one verbal autistic youths and their caregivers. Internal consistency ranged from satisfactory to desirable (α =.74–.92). Convergent validity with medium-large effect size was established using a structured diagnostic interview, the Mini-International Neuropsychiatric Interview for Children and Adolescents (MINI-KID). ASC-ASD scores were positively associated with autistic symptoms and response patterns indicated strong endorsement of autism-specific items. The findings are discussed in relation to existing literature on assessment of anxiety in ASD and in light of the study’s strengths and limitations.