Background: Pretransfusion testing is vital for safe transfusion. However, in situations without time to perform sufficient testing, all or part of the pretransfusion testing may be skipped to issue blood quickly. This study evaluated the safety of red blood cell (RBC) transfusion released by an emergency blood transfusion protocol through retrospective analysis at a tertiary hospital for eight years. Methods: All RBC transfusions following the emergency blood transfusion protocol from 2011 to 2018 at Seoul National University Hospital were included in the study. Crossmatching and unexpected antibody screening test results conducted after RBC release and the occurrence of hemolytic transfusion reactions were analyzed. Results: A total of 1,541 cases (5,299 RBCs issued) of emergency blood transfusion were identified. RBCs were issued after performing the immediate spin crossmatch without an unexpected antibody screening test in most cases (1,443; 93.64%), while RBCs were issued with no pretransfusion testing in 98 cases (6.36%). Antibody screening tests performed after the issue of RBCs showed that 17 (1.1%) cases were positive. Two units of RBCs from two different cases showed positive antiglobulin crossmatch test results. However, none of them were suspected to be associated with a hemolytic transfusion reaction. Conclusion The incidence of incompatible RBC release was very low in patients receiving RBC transfusion through the emergency blood transfusion protocol suggesting it can be used safely with minimal risk of hemolytic transfusion reactions caused by incompatible blood transfusions.