We evaluated the utility of the Japanese version of the Checklist for Autism in Toddlers for predicting pervasive developmental disorders (PDD) among 2-year-old children in clinical settings. Confirmed diagnosis revealed that the pass rate on four items (social interest, proto-imperative pointing, proto-declarative pointing and joint-attention) was significantly lower in 52 PDD children than in 48 non-PDD children, and if abnormal development was reported in two or more items, the sensitivity, specificity, and positive/negative predictive values for PDD diagnosis were 0.85, 0.73, and 0.77/0.81, respectively. This simple screening tool can provide valuable information to clinicians when diagnosing PDD.