Numerous compounds involved in the regulation of the cardiovascular system are also engaged in the control of metabolism. This review gives a survey of literature showing that arginine vasopressin (AVP), which is an effective cardiovascular peptide, exerts several direct and indirect metabolic effects and may play the role of the link adjusting blood supply to metabolism of tissues. Secretion of AVP and activation of AVP receptors are regulated by changes in blood pressure and body fluid osmolality, hypoxia, hyperglycemia, oxidative stress, inflammation, and several metabolic hormones; moreover, AVP turnover is regulated by insulin. Acting on V1a receptors in the liver, AVP stimulates glycogenolysis, reduces synthesis of glycogen, and promotes fatty acid synthesis and acetyl CoA carboxylase activity. Stimulating V1b receptors in the pancreatic islands, AVP promotes release of insulin and glucagon-like peptide-1 (GLP-1) and potentiates stimulatory effects of glucose and ACTH on secretion of insulin. Simultaneously, insulin increases AVP secretion by neurons of the paraventricular nucleus and the supraoptic nucleus. There is strong evidence that secretion of AVP and its metabolic effectiveness are significantly altered in metabolic and cardiovascular diseases. Both experimental and clinical data indicate that inappropriate interactions of AVP and insulin play an important role in the development of insulin resistance in obesity and diabetes mellitus.