Fibrous dysplasia is a rare anomaly of bone tissue development, in which it is replaced by fibrocystic tissue. A clinical case of a patient with a craniofacial polyossal form of fibrous dysplasia is presented. At the age of 13, a child had a constant intense headache, which was accompanied by dizziness, tinnitus, cognitive impairment, deformity of the frontal region and lower jaw on the right, local pigmentation in the neck and face (coffee-and-milk-like stains). Brain tomography and osteoscintigraphy visualized a volumetric formation in the right half of the skull bones, in which fibrotic dysplasia was revealed during histological examination.Conclusion. To establish this diagnosis, a combination of pain syndrome with deformation of the facial part of the skull and histological examination is important.