In recent years, the sunlight vitamin has become extremely popular and almost mandatory to use, especially because of its pleiotropic effects, although until recently its use was limited to the prevention of the development of pathology of the bone system, in particular rickets in children. Being actually a fat-soluble prohormone of a steroid nature, Vitamin D participates in the endocrine, paracrine and autocrine regulation of the body. The pharmacotherapeutic renaissance of calciferol is associated with the discovery of Vitamin D receptors in most cells of the body, and the presence of enzymes synthesizing the active form of Vitamin D extrarenally, in particular, in the skin, has led to renewed interest and broad discussion in the dermatological community. Is the role of non-bone effects of calciferol, mainly its role in the pathogenesis of autoimmune skin diseases, really justified from the point of view of evidence-based medicine, and is the tendency to consume Vitamin D safe?
 This article presents the most up-to-date information about the role of Vitamin D deficiency in the mechanisms of immune response development, in some dermatoses. In addition to generalizing the bone and extra-bone functions of Vitamin D to the macroorganism, the mechanisms of formation of some of the most common dermatoses, such as psoriasis, atopic dermatitis and vitiligo are discussed in detail. The review details the biological effects of Vitamin D in the skin. The article analyzes the legality of the use of Vitamin D-based drugs and their effectiveness in dermatological practice.