Objective: This research was made to personal- social developmental screening of 4-60 months old children in Tehran city by DDST-II and ASQ and determining the agreement coefficient of two tests. Materials & Methods: In this study, the personal-social developmental status of 197 children 4-60 months old were screened by using ASQ and PDQ (93 girls and 104 boys). Convenient sampling was used. Data was analyzed by SPSS software. Results: By using DDST-II and ASQ personal- social developmental delay detected in 11% and 1.5% of children respectively. The estimated consistency coefficient between DDST-II and ASQ for Personal- social domain was 0.06. Conclusion: In this study personal- social developmental screening of children showed different results and kappa measure agreement of two tests was weak. For selecting a suitable tool we must consider the psychometric characteristics (sensitivity, specificity, positive and negative predicting power) of the tool. This study showed that the results of developmental screening of 4-60 months old children in Tehran by using ASQ and PDQ lead to different results. This finding emphasizes the need to comparing the results of screening tests with a diagnostic gold standard test.