The SCQ is a widely used screening measure for the assessment of autism spectrum disorder (ASD). However, its sensitivity and specificity when used with older children in the context of community Child & Adolescent Mental Health services is unclear. Seventy-seven (Mean age = 12.8 years) young people with suspected ASD were screened using parent- and teacher-reported SCQ's before completing a comprehensive diagnostic assessment. Of the 77 young people included, 44 (57%) met criteria for an ASD diagnosis. Our results indicated that regardless of informant, SCQ scores did not significantly predict the outcome of the diagnostic assessment. Based on the published cut-off score for the SCQ, Receiver Operating Characteristic curve analyses revealed a lower than expected sensitivity and specificity. This suggests that the SCQ is not an effective screening tool when used in the context of community Child & Adolescent Mental Health services.