Neurofibromas are common peripheral nerve sheath tumors related to Schwann cell's proliferation and are usually associated with neurofibromatosis type 1. Although solitary neurofibroma that occurs in the paranasal sinus is reported occasionally, neurofibroma located in the frontal sinus is extremely rare. Here, we report a case of a young woman who had a heterogeneous lesion in the left frontal sinus, eroding its anterior and posterior wall with signs of intracranial invasion. Postoperatively, results of the histologic examination confirmed the diagnosis of solitary neurofibroma. In conclusion, solitary neurofibroma should be considered in the differential diagnosis of frontal sinus masses.