Objective: Mental disorders are one of the most frequent disor¬ders in the world. The mental health of prisoners is a major issue of public health. Methods: A cross-sectional study carried at three prisons in Baghdad. All prisoners, both gender were included, using stratified random sampling technique. Socio-demographic variables were collected using an information list filled during the interview. Prisoners' mental state was checked by self-reporting questionnaires scale (SRQ-20). Positive SRQ-20 test prisoners were selected for administration of the DSM-IV Structured Interview by a consultant psychiatrist. Results: Participation rate was 70%; mean age 33.9±7.17 years, bout 50% of prisoners stay in prison between 5-10 years. The prevalence of psychiatric morbidity was 749 (73.9%); obsessive compulsive disorder 1.5%, posttraumatic stress disorder 1.6%, schizophrenia 3.2%, panic disorder 4.8%, generalized anxiety disorder 7.2%, psychosis 9.2%, personality disorder 10.5%, depression 11.9%, and substance abuse 50.1%. Conclusion: The study shows high psychiatric morbidity among Iraqi prisoners that need further attention.