Obstructive sleep apnea syndrome (OSAS) is characterized with recurrent collapse of upper airway during sleep and resulted in hypoxia and sleep fragmentation, which resulted in cardiovascular diseases, metabolic disorders and neurocognitive dysfunctions. The cardiovascular complications attributed to OSAS included hypertension, coronary artery disease, heart failure and stroke. The mechanisms responsible for developments of cardiovascular sequelae included repeated episodes of hypoxia and hypercapnia, exaggerated negative intrathoracic pressure and bursts of sympathetic activity provoking surges in blood pressure and heart rate. Increase of inflammatory mediators, which included C-reactive protein, oxidative stress, adhesion molecules, vascular endothelial growth factor and proinflammatory cytokines, were thought to involve in the developments of cardiovascular diseases in patients with OSAS.