Introduction <p>Road traffic crash injury is a global burden of mortality and disability, mainly in developing countries, including Ethiopia. However, in Ethiopia, there is a limitation of investigation regarding the survival status of road traffic victims.</p> Objectives <p>This study aimed to estimate the thirty-day mortality and its predictors in Addis Ababa, Ethiopia.</p> Method <p>An institutional-based follow-up study was conducted on 373 randomly selected crash victims in Addis Ababa hospitals. The study was conducted from February 2022 to August 2022 by interviewing victims and reviewing the injured patient charts using a valid data extraction checklist. The participants were followed for 30 days for survival status. Descriptive statistics, including median, interquartile range, frequency, and the Kaplan-Meier survival curve, were used. For inferential statistics, the Cox proportional hazard regression was used. The patient charts were kept confidential.</p> Result <p>The incidence rate for 373 was 2.71 per 10,000 person-hours of observation. The majority of patients, approximately 210 (56.3%), were in the 18- to 30-year-old age group. A male-to-female ratio was 3:1. The highest number of deaths was observed in the male group, 56 (19.9%). The most common fatality occurs among patients with multiple injuries. For participants who had extremity injury, the hazard of death was decreased by 80% (AHR = 0.20, 95% CI: 0.07–0.51, P-value &lt; 0.001). Those patients who had oxygen saturation status greater than or equal to 95% had a reduced hazard of death by 65% (AHR, 0.35, 95%CI: 0.17–0.71; P-value &lt; 0.003).</p> Conclusion <p>The incidence of 30-day mortality of crash victims was high (2.71 per 10,000 person-hours of observation) in Addis Ababa, Ethiopia. Being young, male sex, penetrating injury, and hypoxia were associated with death. Participants with head/neck injuries had high crash mortality. It is better to strengthen prompt care by utilizing the necessary healthcare resources.</p>