Unplanned emergency department (ED) revisit is one of the major challenges faced by emergency care facilities and reflects their quality of care. It is an important key performance indicator (KPI) for emergency medical care. Often, inadequate medical care by physicians is claimed to be the main cause of unplanned ED revisits, yet this assumption is not well studied in the literature. Thus, this study aimed to identify the causes of unplanned ED revisits within 72 hours from the initial visit to the emergency department which could help in developing an action plan and improve quality of care and patient safety.A retrospective study was conducted in Rashid Hospital Trauma Center, from December 2019 to January 2020, using electronic medical records reviewed by two independent investigators. The reasons for the ED revisits were categorized into the following four domains: illness, physician, patient, and system related. A total of 584 revisits were found which accounted for 1.9% of ED attendance from December 2019 to January 2020. Majority of them were male patients, and 63% of the population had a mean age of 33 years. Majority of the ED revisits were due to illness (54%), followed by patient related (20%), physician related (18%), and system related (8%) factors. Most of the patients were discharged on the second visit. The two most common reasons for revisits in the ED department that were seen within the 72 hours were illness related and patient related, followed by physician related. The cause is mainly rooted in suboptimal discharge plans.