BACKGROUND: Little is known about acute and transient psychotic disorders, which is a diagnostic group, introduced with International Classification of Disease, 10th revision. It is an interesting area of research receiving a lot of attention. OBJECTIVE: The aim of the study was to find the incidence of acute and transient psychotic disorders in the population and determine its sociodemographic features in the State of Qatar. Design. This is a retrospective descriptive study. Setting. The study was conducted in the Department of Psychiatry of the Rumaillah Hospital, Hamad Medical Corporation, Doha, Qatar. METHODS: All Qatari, non-Qatari Arabs, and expatriate patients who were hospitalized with psychotic disorders in the inpatient wards or treated in the outpatient clinics of the Department of Psychiatry over a 7-year period were enrolled in the study. Data were collected from the medical records of patients. The study was conducted from August 1, 1996, to January 1, 2004, amongst the patients with acute and transient psychotic disorders. The diagnostic classification of definite psychotic disorders was made in accordance with criteria based on the International Classification of Disease, 10th revision (ICD-10). RESULTS: A total of 174 patients were treated during a 7-year period. Among them, 69% were males and 31% females. No cases were found in children aged less than 15 years. The highest frequency (43.7%) was found in the early adulthood (16-29 years of age). The incidence of acute and transient psychotic disorders was higher in the expatriates (66.7%). More than half (63.8%) of the patients were employed. Most of the cases (35.6%) had acute schizophrenia-like psychotic disorders (F23.2). There was no statistically significant difference in the frequency of acute and transient psychotic disorders between males and females, Qatari and non-Qatari Arabs, and single and married. CONCLUSION: The study found markedly lower incidence rate of acute and transient psychotic disorders in females than males. The highest frequency was found in the early adulthood (16-29 years). No cases were found in children aged less than 15 years. It is important to find ways to promote healthier lifestyles in this population in order to prevent the onset of psychotic disorders.