Purpose: To investigate the status of protein supply by comparing the recommended amount with the delivered amount of protein in patients in the trauma and surgical intensive care units (ICU). Feedback on the protein supply status was presented to each hospital, and we evaluated whether the protein supply had increased to an appropriate level.Methods: In this retrospective observational multicenter study, nutritional information on patients in the trauma and surgical ICUs who had received nutritional support intervention was collected on the 1st Wednesday of each month at two-month intervals from August 2020 to June 2021, from nine domestic hospitals in Korea. Every two months, the nutritional status of each hospital was shared with all hospitals, and each nutritional support team received feedback on protein supply status.Results: There were 246 patients from nine hospitals included in this study, and data over the study period from six protein days, were analyzed. The mean ratios of delivered calories to calculated required calories were 74.0%, 80.8%, 85.4%, 77.9%, 71.3%, and 82.1% on Protein Days 1, 2, 3, 4, 5, and 6, respectively. The mean ratios of delivered protein to calculated required protein were 73.0%, 77.2%, 78.9%, 79.3%, 69.4%, and 89.6% on Protein Days 1, 2, 3, 4, 5, and 6, respectively.Conclusion: Protein supply increased to an appropriate level, feedback on protein supply status may have increased the protein supply ratio and promoted appropriate protein supply and nutritional support for patients in the trauma and surgical ICUs.