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Background: Fibrous dysplasia (FD) is a developmental anomaly of unknown pathogenesis in which normal bone is replaced by an abnormal fibrous tissue. The process may affect a single bone (monoostic form of fibrous dysplasia) or multiple bones (polyostic form). The skull is the second most common site of FD and comprises 25% of cases. The purpose of this article is to evaluate the usefulness of CT and MRI in diagnostics of cranial fibrous dysplasia lesions. Material/Methods: We analyzed 13 CT and 6 MR examinations performed in 9 females aged 40 to 73 years (mean age 54.7 years). Four patients were referred to the examinations with a diagnosis of fibrous dysplasia, 3 others -with a suspicion of neoplastic disease and 2 patients - with no preliminary diagnosis. Clinical symptoms included: headache, deformity and asymmetry of craniofacial region. Results: Fibrous dysplasia lesions were unilateral in 8 patients; in one patient they were bilateral. The sphenoid and ethmoid bones were the most common single bones involved by FD lesions. Among 9 cases of FD, orbital involvement was found in 8, nasal sinuses and cavity involvement in 6 and intracranial extension in 3 patients. Conclusions: CT and MR are useful in confirming the diagnosis of FD and especially in evaluating the extent of the disease.