In recent years, the problem of hyperprolactinemia in children remains relevant because it is one of the most common pathologies of the hypothalamic-pituitary system, causing impaired fertility and reproductive function in adulthood. According to population studies, its incidence is 0.5 % in females, exceeding this figure in males by 10 times. Prolactin has: immunomodulatory effect, enhancing lymphocyte proliferation, phagocytic capacity of macrophages, IgA synthesis; analgesic effect; promotes postnatal growth of the body by inducing the activity of genes associated with growth; activates the proliferation of keratinocytes, epithelial cells of the prostate; participates in the regulation of metabolism, water-electrolyte balance, inhibiting the excretion of potassium and sodium ions by the kidneys; influences human behavior by accelerating neurogenesis, memory, learning and providing neuroprotection; induces surfactant production; stimulates lipogenesis. Prolactin levels increase due to physiological hyperestrogenemia, which blocks the inhibitory effect of dopamine on prolactin secretion and occurs during lactation, pregnancy and some other physiological states. Pathological hyperprolactinemia occurs in children with secondary hypogonadotropic hypogonadism, organic lesions of the suprasellar area of the brain and may be secondary (symptomatic). In the etiological structure of hyperprolactinemia syndrome, the largest proportion (60 %) in children and adolescents belongs to prolactinomas (pituitary adenomas that secrete prolactin), idiopathic hyperprolactinemia (22.7 %) and iatrogenic hyperprolactinemia induced by 6 drugs (4 % of cases). Given that the lion’s share of hyperprolactinemia in childhood is associated with the presence of pituitary prolactinoma, characterized by latent gradual progression of reproductive disorders, growth processes and neurological symptoms, the objective of this article is to focus on the pleiotropic effects of prolactin in the body, which controls more than 300 biological functions, epidemiological, etiological and pathogenetic mechanisms, on the features of the clinical classification of hyperprolactinemia to form a modern understanding of this problem.