Monogenic hypertension (MH) is a rare form of arterial hypertension (AH) in which a single gene mutation is responsible for developing the disease. This article discusses the pathogenesis, genetics, phenotype, and treatment of monogenic forms of AH. According to Guyton's hypothesis, mutations responsible for MH development most often lead to increased renal sodium reabsorption, in a mineralocorticoid-dependent or -independent mechanism, resulting in fluid retention and increased blood pressure. MH most often appears in childhood or adolescence and is characterized by moderate to severe blood pressure elevation and resistance to standard treatment. The coexistence of water-electrolyte abnormalities, most commonly hypokalemia and metabolic alkalosis, is characteristic but not always present. Monogenic AH should also be considered in patients with precocious or delayed puberty, growth deficiency, brachydactyly, and severe symptoms or hypertension mediated-organ damage. Identifying patients with monogenic hypertension is of utmost importance to implement appropriate treatment and reduce the risk of cardiovascular complications.