The aim of this study was to evaluate the reliability and validity, as well as the specificity, of the Greek version of the Calgary Depression Scale for Schizophrenia (CDSS). Schizophrenic inpatients consecutively admitted at the Eginition Hospital, University of Athens, were included in the study. Patients were assessed on admission using the CDSS, the Hamilton Depression Rating Scale (HDRS), the Positive and Negative Syndrome Scale (PANSS), the Rating Scale for Extrapyramidal Side Effects (RSESE), the Rating Scale for Drug-Induced Akathisia (RSDIA) and the Abnormal Involuntary Movement Scale (AIMS). The CDSS was found to have a high inter-rater reliability, as well as test-retest reliability or split-half reliability. The internal consistency of the CDSS was good (a=0.87). There were positive correlations between the CDSS and the HDRS, or the depression cluster of the PANSS. The mean score on the CDSS showed no significant correlations with that of the PANSS negative subscale (r=0.123); a negative but not significant correlation with that of the PANSS positive subscale (r=-0.036); a weak correlation with that of the PANSS general psychopathology subscale (r=0.218); and no significant correlations with that of the RSESE (r=0.197), the RSDIA (r=0.160) or the AIMS (r=0.031). Our results give further support to the reliability, the validity, and the specificity of the CDSS.