Autoimmune diseases commonly develop in women, and therefore the role of estrogens and androgens in the regulation of autoimmunity has long been suggested and is well explored. Despite numerous studies, the role of prolactin in the development of autoimmune diseases remains a subject of debates. However, cells of the immune system do express prolactin receptors on their surface and are activated upon binding to the corresponding ligand. Also, prolactin is produced by the immunocompetent cells themselves, and, in addition to the systemic (endocrine) mode of signal transmission, can act locally: with paracrine and autocrine modes. Prolactin is able, synergistically with interleukin-2, to trigger the proliferation of T, B and NK cells, it stimulates the production of interferon-γ by T-lymphocytes, promotes the maturation of dendritic cells, increases antibody synthesis and regulates the processes of B-lymphocyte immunotolerance, in addition to other hormonal effects. This review analyzes the scholarly publications of the last five years, revealing the relationship between prolactin and the occurrence of various immunopathological diseases, especially autoimmuneones. Pathogenetic roles of huperprolactinemia in hypophysitis and hypothyroidism (bibliography: 93 refs).