Background: Traumatic head injury, referred to as the “silent epidemic”, remains a growing public health concern and the leading cause of mortality in young adults, with a disproportionate burden of disability and death occurring in low-income and middle-income countries, including Ethiopia. However, estimates of the traumatic brain injury burden from low and middle-income countries are scarce. The aim of this study was to assess outcome and its associated factors among patients with head injury admitted to the Adult Intensive care unit at AaBET and ALERT hospitals, Addis Ababa, Ethiopia. Methods: Institution-based retrospective cohort study was conducted at AaBET and ALERT hospitals from February 01, 2019 to January 30, 2020. All head injury patients’ records were reviewed. A structured checklist was used to collect data. Binary logistic regression analysis was used to identify factors associated with death among head injury patients. Result: Out of 205 patients, 178 (86.8%) improved, while 27 (13.2%) died. Road traffic accident was the most common cause of head injury (Adjusted odds ratio (AOR) = 46.3%). Patients with pulse rate admission (AOR = 1.49), NA + level (3.48), type of head injury (AOR = 3.67), mechanical ventilation (AOR = 4.70) were significant predictors of death among patients with head injuries. Conclusion: The incidence of death among head injury patients was 13.2% (27). Road traffic accident was the leading cause of head injury. Pulse rate, plasma sodium level, penetrating head injury, being on a mechanical ventilator were predictors of death among traumatic head injury (THI) patients treated for head injuries. Prevention of road traffic accidents and continuous awareness creation about the consequences of a road traffic accident is recommended.