The purpose of the study is to develop a comprehensive risk score of mortality in trauma victims that can predict the in-hospital mortality better than trauma injury severity score (TRISS) and A Severity Characterization of Trauma (ASCOT) score. All hospitalized trauma patients, between the ages of 16 and 89years old were included in the study. The National Trauma Quality Improvement Program (TQIP) database of the calendar year 2011-2016 was accessed for the development of a traum mortality scoring system (TMS). The prediction of mortality was tested by creating a receiver operating characteristics (ROC) curve and an area under the curve (AUC). ROCs and AUCs of TMS were compared with TRISS and ASCOT score. The AUC of TMS (0.892, 95% CI: 0.888-0.896) was better than TRISS (0.864, 95% CI: 0.859-0.869, P <0.0001) and ASCOT (0.841, 95% CI: 0.835-0.846, P <0.0001), respectively, in blunt injury. Similarly, TMS prediction (AUC: 0.949, 95% CI: 0.940-0.958) was better in penetrating injury when compared with TRISS (0.942, 95% CI: 0.934-0.951, P = 0.030) and ASCOT (0.924, 95% CI: 0.912-0.936, P <0.0001), respectively. TMS can predict the in-hospital mortality better than TRISS and ASCOT.