Hydrogen sulde (H₂S) is a novel endogenous gaseous signal molecule, and plays important role in both physiological and pathophysiological processes including vasodilation, regulation of blood pressure and angiogenesis, anti-oxidation and cardioprotection. The underlying mechanisms involve in induction of S-sulfhydration, modulation of autophagy and miRNA expression, regulation of ion channels, SIRT1 and Nrf2 activity, interaction with NO and CO signaling. It has been shown that decrease of endogenous H₂S level links to a variety of cardiovascular diseases such as hypertension, atherosclerosis, myocardial ischemia and reperfusion injury and heart failure. Increased endogenous H₂S production or administration of exogenous H₂S is a new strategy for prevention and treatment of the cardiovascular diseases. This review mainly focuses on the recent progress about the role and mechanisms of hydrogen sulfide in cardiovascular system.