Transfusion-related acute lung injury (TRALI) is one of the leading causes of transfusion-related morbidity and mortality. However, it is frequently not diagnosed and under-reported, which could result in inappropriate treatment. Diagnostic definition for TRALI consists of hypoxia and bilateral pulmonary edema occurring during or within 6 hours of a transfusion in the absence of cardiac failure or intravascular volume overload. Here, we report a fatal case, which resulted from under-recognition and misdiagnosis of TRALI occurring during transfusion with packed red blood cells during a bilateral total knee replacement.