Cystic angiomatosis is a rare disease characterized by disseminated multifocal hemangiomatous and/or lymphangiomatous cystic lesions of the skeleton with possible visceral organ involvement. Only a few dozens of such patients worldwide have been described in the literature. This article presents two case reports of the patients admitted to the D. Rogachev NRMCPHOI with suspected Langerhans cell histiocytosis. The patient’s parents gave their consent to the use of their child’s data, including photographs, for research purposes and in publications. During the investigation, multiple cysts of the skull bones, spine, pelvic bones and limbs, as well as of the spleen were found in both patients. A biopsy of the bone cysts of the skull revealed no data in favor of histiocytosis or other neoplasms. Cystic angiomatosis was diagnosed in both cases. This is a rare disease that should be kept in mind in the differential diagnosis in patients with cystic lesions of the bones and visceral organs.