The purpose of this study was to determine the proportion of cases thought to have a mental disorder, and/or proposed treatment. Additionally, we assessed the relationship between age and sex regarding mental disorders, and the treatments recommended to patients diagnosed as mentally ill by their physicians.During a one year period the out-patient polyclinic registration lists of 313,139 patients attending primary health care clinics in the centre of Eskişehir were scanned by the researchers.The proportion of mental disorders in patients attending primary care centres at least once owing to a mental disorder was 2.34%. However, this proportion in patients attending once was 1.04%. Compared with men, women attended primary care clinics more frequently. The most common diagnoses were depression and anxiety disorders; these were more frequent in women than in men. The most frequently prescribed medicines for mental disorders were anxiolytics and antidepressants.The low levels of diagnoses and treatments of psychiatric disorders in primary care settings are thought to be associated with the following: physicians under-recognising mental disorders despite being educated about this subject, mental screening scales not being used, patients being unaware of their diseases and giving insufficient information to physicians about mental symptoms, co-occurrence of medical diseases and psychiatric problems, the physicians' negative approach to patients, and the physicians' tendency not to give importance to drug or medical records.