Objective: To investigate the role of red cell distribution width (RDW) in comparison with Trauma-Associated Severe Hemorrhage (TASH) system in predicting the mortality of multiple trauma patients, referred to the hospital emergency department.Methods: This follow-up study was conducted on multiple trauma patients (age ≥ 18 years) with Injury Severity Scores (ISS) of ≥ 16, who were referred to the emergency department from March 1, 2017, to December 1, 2017. First, all patients were evaluated based on the Advanced Trauma Life Support (ATLS) guidelines, and then, their blood samples were sent for RDW measurements at baseline and 24 hours after admission. The ISS, Revised Trauma Score (RTS), and TASH were measured in the follow-ups and recorded by third-year emergency medicine residents. Hospital mortality was considered as the outcome of the study.Results: In this study, 200 out of 535 multiple trauma patients were recruited. The frequency of hospital mortality was 19 (9.5%). In the univariate analysis, there was no significant relationship between hospital mortality and RDW at baseline, RDW on the first day, and ΔRDW (RDW at baseline - RDW on the first day), unlike ISS, RTS, TASH (p=0.97, P= 0.28, and p=0.24, respectively). On the other hand, in the multivariate analysis, ISS, RTS, and TASH showed a significant relationship with hospital mortality. The greatest area under the ROC curve (AUC) was attributed to TASH and RTS systems (0.94 and 0.93, respectively).Conclusion: TASH scoring system, which was mainly designed to predict the need for massive transfusion, may be of prognostic value for hospital mortality in multiple trauma patients, similar to ISS and RTS scoring systems.