Traumatic brain injury (TBI) is an important cause of morbidity and mortality especially in low-and-middle income countries (LMICs). The study objective was to assess causes and outcomes of intentional TBI among patients presenting to a tertiary-care hospital in Uganda. The study site was Mulago National Referral Hospital, Kampala, Uganda. Data was collected from May 2016-July 2017. Patients of all age groups presenting to emergency department of the hospital with suspected or documented TBI were enrolled. Patient demographics, TBI causes and outcomes were recorded. TBI was grouped into mild (13–15), moderate (9–12) and severe (≤8) categories based on Glasgow Coma Scale (GCS). Ethical approval was taken from Johns Hopkins School of Public Health and Makerere University. Out of 3749 patients with known intent, 30.3% (n=1135) had intentional TBI. Majority were males (84.5%); mean age was 28.5±14.5 years. Assault (97.1%) was the main cause, however, there were 33 (2.9%) cases of self-harm. Common assault methods were use of bodily force (33.7%), iron bar (24.2%) and hammer (12%). Gun was used in 3 cases. About 60.9% of these victims were breadwinners. 62.8% were in mild GCS category, 22.4% in moderate and 14.9% were in severe category. About 42.6% of the patients were admitted to ward, 37.1% were sent home. There were 30 deaths; 29 were assault victims and 1 of self-harm. Intentional TBI is common among young males in Kampala with assault being the main cause of TBI. TBI resulting from assault among young males in Kampala is an important cause of mortality and morbidity. This has consequences for LMICs like Uganda which has a young population contributing to a broad population pyramid. There is need for further exploration of intentional injuries among youth in the country and to develop programs to engage youth in productive activities for contribution towards country’s economic development.