Background: Severe traumatic brain injury (TBI) is associated with a high mortality and morbidity rate and is one of the leading causes of death in the intensive care units. The aim of this study was to examine predictors of hospital outcome in adult patients admitted to ICU because of severe TBI. Methods: A retrospective study was carried on patients (n=621) with severe head injury, defined as Glasgow Coma Scale (GCS) ≤ 8 who were admitted to the general ICU over a 15-year period (1999-2013). Most important variables that could be correlated with outcome (demographics, cause of injury, GCS, clinical variables and computed tomography–CT scan) were analysed. Results: Total mortality rate was 27.38%. Patients older than 75 years had a mortality rate of 57.14%. 70.05% of the patients were male and 61.99% of cases were due to traffic accidents. Coexisting injuries, found in 52.98% of the patients aggravated the prognosis. Shock developed in 17.23% of the patients and hypoxia in 27.38% were especially aggravating factors.