Case report of a 29-year-old woman with an psammomatoid ossifying fibroma of the left frontal sinus. Headache was the presenting clinical symptom. The tumor and its intracranial extension were identified by computed tomography and magnetic resonance tomography. Through a two-step combined neuro-rhinosurgical operation the tumor could be completely removed. Ossifying fibroma is a benign tumor mostly affecting the mandible and maxilla. A more aggressive approach may be more beneficial than expectant observation or curettage in the initial management of this benign neoplasm. Because of the unusual location of this rare entity the case history is published and differential diagnostic and therapeutical implications are discussed.