Renin-angiotensin system (RAS) antagonists (angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers) are now widely used in the clinical practice. Though arterial hypertension remains the most important indication for these drugs, many major clinical studies showed their organ protecting properties which are not completely dependent on antihypertensive action. They manifest with effective preventing of progressing and even partial regression of target organ damage with pronounced cardio-, angio- and renoprotective action. This served a basis for usage of RAS antagonists in patients after myocardial infarction, at the presence of cardiosclerosis and heart failure. Multidirected action of these drugs is manifested also by their ability to improve metabolic disturbances, especially changes of lipid and glucose metabolism, by prevention of the development and progression of type 2 diabetes mellitus and atherosclerosis. Analysis of the contemporary literature is devoted not only to the description of the RAS antagonists effects but also to the mechanisms of their pleiotropic action which are basis for their therapeutic effects.