Abstract Background Blood transfusion is a common therapy for multiple trauma patients, and is often performed soon after hospital admission. It is unclear whether the need for a blood transfusion in multiply injured patients presenting with a positive blood alcohol concentration (BAC) is associated with increased morbidity/mortality, since their risk behavior differs significantly from patients with a negative BAC. In this study, we evaluated the role of blood transfusion in the treatment of BAC-positive multiple trauma patients. Patients In a three-year period, 164 patients at a single trauma center presented with a positive BAC, and 145 met the inclusion criteria for further evaluation and regression analysis. We compared patients who were transfused (n = 76) with those who were not transfused (n = 69). Results In both groups, the most common causes of trauma were traffic accidents and falls. Most patients were admitted to the hospital from the scene of the accident (77.2%) and were male (89.0%). Transfused patients had a lower GCS (p ≤ .001) and her ISS (p ≤ .001), were more likely to have severe head injuries (p ≤ .001), tended to have higher BACs (p = .053), had lower hemoglobin levels and prothrombin times in the first 24 hours (p ≤ .001), had lower lactate levels, had higher rates of intubation (p ≤ .001) and ICU admission, and had longer ICU stays and artificial ventilation times (p ≤ .001). Mortality was significantly higher in transfused patients (n = 15 vs. n = 3, p ≤ .001). Non-survivors were more likely to have severe head injuries; be intubated and ventilated; be older; have higher ISS scores, lactate levels, and numbers of transfusions in the first 24 hours; and have lower GCS scores, hemoglobin measurements, and prothrombin levels. In a binary logistic regression model, only age (p = .009) and ISS (p = .004) independently predicted mortality. Conclusion In our single-center study, the BAC of multiple trauma patients and the number of blood transfusions they received did not predict mortality in multiple trauma patients if used as independent predictors. Prospective studies with greater sample sizes should be performed to clarify the role of blood transfusions in the outcome of this sub-population.