The purpose of the present study was to determine the prevalence of mental disorders in general practitioners (GPs), internist, neurologists and psychiatrists private clinic. Samples were 400 (163 male, 237 female) who were selected randomly from four private clinics. The instrument used in this study was SRQ-20 Questionnaire. Results showed that the prevalence of mental disorders was 51% (49.1% for male, 52.3% for female). The prevalence of mental disorders in psychiatric clinics was 80%, in internist clinics 48%. In GPs clinics 43% and in neurological clinics 33%. The findings indicated that with excluding the psychiatrist's clinical prevalence of mental disorders in other clinics was 41.3%. Furthermore people who visited by psychiatrists had higher scores on SRQ-20 than others.