Background: Injury becomes life threatening community health problem associated with significant mortality and morbidity worldwide. Road traffic accident is the most commonly encountered trauma and the leading cause of death and disability from injuries in Ethiopia. The aim of this study is to assess the epidemiology and outcomes of injury in Ethiopian University Hospital. Methods: Institutional based retrospective cross-sectional study was conducted from January 2015 to June 2019. Data was collected using questionnaire adapted from WHO injury surveillance guideline. Bivariate and multivariate logistic regressions were performed to determine factors associated with hospital mortality. Results: A total of 376 trauma cases were included in the study. The majority of 196(52.1%) victims were in the age range of 20-40 years. Road traffic accident was the commonest mechanism of injury 178(47.3%) followed by interpersonal violence 113(30.1%). The majority of patients 135(35.9%) had associated with lower extremity injury and there was 23(6%) mortality in this study. Revised trauma score (RTS) < 10 (AOR=2.5; 95% CI, 1.8-25.6), Glasgow coma scale (GCS) (AOR =0.3; 95% CI, 0.13-0.5), Length of hospitalization (LOS) 1-7 days (AOR=0.1; 95% CI, 0.01-0.8), and Time to arrival >24hr were predictors of mortality in a patient with injury. Conclusion: A lower extremity injury was common and mostly associated with RTA. Length of hospitalization > 7 days, RTS<10, decrease GCS and time to arrival >24hr were factors associated with mortality. Pre-hospital emergency medical service system and trauma registry needs to be established to decrease burden of injury. Keywords: Injury, Epidemiology, Outcome, Ethiopia