Abstract: Objective: To explore the clinical, radiographic and pathological diagnosis of fibrous dysplasia of bone (FD) and ossifying fibroma (OF) for improving the diagnosis accuracy. Methods: Clinical file records, radiographs and pathological slices of the 25 cases FD and 16 cases OF were analyzed. Results: Ages of patients have no difference(mean 22.56 years in FD and 28.25 years in OF). The ratio of male to female is 1∶1, the later is 5∶3. The maxilla was involved far more often than the mandible (72% and 62.5%, respectively), most common in the posterior region of the maxilla. Radiographically, ossifying fibroma mostly was mixed radiolucent–radiopacity. Fibrous dysplasia mostly appeared as a radiopaque lesion. Although FD often showed immature trabecular bone formation differentiated to mature trabecular bone of OF, there is the same pathological appearance in mature type of FD and OF. Conclusion: It is necessary to differentiate FD and OF by comprehensive study the clinical cases, X rays and pathological slices.