Background: This study screened children in Beijing, China, in order to establish the validity of a Mandarin Chinese translation of the ASSQ. Methods: We recruited children diagnosed with autism spectrum disorders (ASDs), attention deficit/hyperactivity disorder (ADHD), childhood-onset schizophrenia (COS) (DSM-IV diagnoses made independently by two senior psychiatrists) and unaffected children attending a public school in Beijing. Their parents were asked to complete the CH-ASSQ. Results: Data from the parents of 94 children with ASD (mean age: 81 plus or minus 47 months), 45 with ADHD (106 plus or minus 27 months), 26 with COS (166 plus or minus 36 months), and 120 unaffected control (72 plus or minus 16 months) were collected. The total scores of ASSQ in children with ASD, ADHD, COS, and unaffected controls were 25.3 plus or minus 9.2, 10.4 plus or minus 7.1, 12.2 plus or minus 10.6, and 5.2 plus or minus 6.6 respectively. Total ASSQ scores of children with ASD were significantly higher than in any other group (all p less than 0.0001). ROC analysis of ASD versus unaffected control subjects showed the area under curve was 0.957, with a cutoff of 12 having the maximum sensitivity (0.957) and specificity (0.825). Conclusions: Our pilot data suggest that CH-ASSQ successfully differentiates clinically diagnosed ASD patients from unaffected controls, as well as from patients with ADHD and COS. The instrument might therefore be useful for screening for ASD in urban Mandarin Chinese-speaking populations. (Contains 1 figure and 3 tables.)