The article presents basic information about cutaneous leiomyoma - a rare benign tumor of the skin from smooth muscles. The most common leiomyomas of the skin from the muscles that raise the hair, which are inherited in an autosomal dominant manner, manifest mainly in adulthood and occur in men 2 times more often than in women. The clinical picture is characterized by nodules of a hemispherical shape, densely elastic consistency, flesh-colored, pink and red in color with a brownish or bluish tinge, ranging in size from 0.1 mm to 2 cm in diameter, with a smooth and shiny surface, which are located asymmetrically, isolated or grouped on the scalp, lateral surfaces of the neck, trunk and lower extremities. It is known that the most common complaint in patients is pain of varying severity in the area of the nodules. Pain of varying severity in the area of nodules is the most common complaint in patients and can occur spontaneously or be provoked by any mechanical irritation of the skin, cold, as well as emotional stress. This pain syndrome in patients has been well studied and described in clinical practice, at the same time, there are no indications in the specialized dermatovenerological literature of the occurrence of pain in patients during sleep.The case of the diagnostics of cutaneous leiomyoma of the muscles lifting hair is presented in a 66-year-old patient who consulted a dermatovenerologist at the clinic of the Ural Research Institute of Dermatovenereology and Immunopathology. The diagnosis was verified by a pathomorphological study of a skin biopsy. A detailed study of the patient's anamnesis and complaints revealed episodes of unbearable pain in the projection of rashes that occur during emotionally colored dreams. A new clinical syndrome of the disease is described - myalgia in the rem sleep, which can be explained by the predominance of the sympathetic nervous system and the activation of physiological functions of the body during dreams.