The aim of the study was to find out the validity and reliability of the Turkish version of the Edinburgh Postnatal Depression Scale (EPDS) and to determine the optimum cut-off value for postnatal depression. Method: Validation of the Turkish version of the EPDS was conducted on a sample of 341 women who were within their first postpartum year. Structured Diagnostic Interview for DSM-IV Axis I Disorders was used as the gold standard test, and receiver operating characteristic analysis was used to evaluate test performance of the EPDS. Results: The study of sensitivity, specificity and predictive values versus SCID-I indicated a cut-off score of 12.5 as the best (sensitivity: 75.5, specificity: 71.5). Positive predictive value was 30.3% and negative predictive value was 94.5 %. Cronbach’s alpha value was calculated as 0.72. Conclusions: It was concluded that: (1) values for the validity were respectable, but not excellent; (2) the scale needs to be improved for use in the Turkish population; and (3) the high prevalence of postnatal depression found in this study may be a function of the low validity of the test.