ObjectiveTo discuss the clinical manifestations, diagnosis and treatment of ossifying fibroma(OF) of the mastoid process by reporting a rare case and reviewing the relevant literature, so as to improve the understanding of this disease and reduce missed diagnosis and misdiagnosis.MethodsA female patient with ossifying fibroma of the mastoid was reported, who was admitted to hospital on August 24, 2020. After clinical and imaging examinations were performed, and the mastoid tumor was removed under general anesthesia. Postoperative follow-up was 12 months.ResultsThe postoperative pathological diagnosis was of ossifying fibroma.The patient recovered without vomiting, vertigo and facial paralysis. After 12 months of follow-up, the patient did not complain of headache, tinnitus and other discomfort, and no recurrence.ConclusionOF is rare to occur in the mastoid of temporal bone. There is no obvious clinical manifestations in the early stage of the disease, which is easy to be missed. This paper emphasizes that in ossifying fibroma: imaging and histopathological analysis is the main basis of diagnosis and classification. Surgical resection is a preferred selection when the patient develops clinical manifestations, and the specific treatment method of OF should be flexibly selected according to the mass size, limitations, degree of invasion, involvement of surrounding structures, clinical manifestations, prognosis and tolerance of patients.