Apart from nitric oxide (NO) and carbon monoxide (CO), hydrogen sulfide (H2S) is the third gaseous mediator in mammals. H2S is synthesized from L-cysteine by cystathionine β-synthase (CBS), cystathionine γ -lyase (CSE), or by sequential action of alanine aminotransferase and 3-mercaptopyruvate sulfurtransferase. In the cardiovascular system, H2S is involved in the regulation of vascular tone and blood pressure, inhibits atherogenesis, and protects myocardium from ischemia-reperfusion injury. Recently, the first organic, water-soluble H2S donor, GYY4137, has been synthesized. In addition, H2S-releasing derivatives of several currently used drugs such as sildenafil, diclofenac, aspirin and mesalamine were obtained. Such compounds may be used in the future treatment of cardiovascular diseases. In this article, we describe the role of H2S in the regulation of blood pressure and in the pathogenesis of arterial hypertension and atherosclerosis which are two most common cardiovascular disorders.