Reperfusion injury is recognized as a syndrome which impairs an ischemic organ as well as remote organs throughout the entire body. Previous research has revealed that the various inflammatory mediators, such as cytokines, platelet-activating factors, and free radicals, are involved and interact with each other in reperfusion injury. More recently, it has been demonstrated that neutrophils play an important role in the development of reperfusion injury. Thus the process of reperfusion injury is quite similar to that observed during the acute phase of inflammation. The same systemic reaction is also observed in multiple organ failure (MOF) or systemic inflammatory response syndrome (SIRS), where organ failure is a major determinant factor for the prognosis of patients. Regarding the treatment of organ failure due to reperfusion injury, several approaches using monoclonal antibody of adhesion molecules or receptor antagonist for cytokines have been introduced. Despite the current accumulation of knowledge, however, prevention is still the regimen for reperfusion injury and concomitant organ failure.