Purpose: Coronary reperfusion by primary percutaneous coronary intervention (PCI) has been established as an essential therapy of ST-elevation myocardial infarction (STEMI). Although the coronary intervention is undoubtedly beneficial, reperfusion itself can induce processes resulting in additional myocardial damage - a phenomenon known as ischemia-reperfusion injury (IRI). Oxidative stress is one of the major factors contributing to IRI. This systematic review focuses on the effect of antioxidant therapy on reperfusion triggered oxidative stress and myocardial IRI in patients with STEMI. Methods: We performed a systematic search in EMBASE and Pubmed and included eight randomised clinical trials evaluating edaravone, allopurinol, vitamin c, nicorandil, N-acetylcysteine, glucose-insulin-potassium, atorvastatin and deferoxamine. Results: Administration of edaravone, allopurinol, atorvastatin and nicorandil as a supplement to primary PCI significantly reduced oxidative stress and myocardial damage as well as improved cardiac function and clinical outcomes. Treatment with deferoxamine and N-acetylcysteine reduced the oxidative stress but an effect on the clinical outcome parameters could not be shown. Conclusions: Preliminary studies of edaravone, allopurinol, atorvastatin and nicorandil seems promising though larger clinical trials with a wider range of clinical outcome parameters and trials of higher methodological quality should confirm the clinical benefits before a general recommendation can be given. Moreover, the included studies revealed a complex link between oxidative stress and cardiac function and/or cardiac adverse events and in order to further elucidate the detrimental role of oxidative stress in IRI in relation to primary PCI the assessment of oxidative stress and the clinical outcome parameters should be standardized.