Obstructive sleep apnoea syndrome (OSAS) is characterised by repeated episodes of upper airway occlusion during sleep.It can cause cycles of hypoxia reoxygenation. And it was postulated that intermittent hypoxia seems to resemble ischemia-reperfusion.Many study suggest that ischemia-reperfusion represents an oxidative stress causing increased generation of reactive oxygen species, especially superoxide anions.It is one of the most important mechanisms of cardiovascular diseases, including hypertension, coronary artery disease and cerebrovascular accident complication with OSAS.So many individuals approve OSAS is an Oxidative Stress disease.