An unusual case of malignant schwannoma with involvement of the forehead, external nose, right nasal cavity, paranasal sinus system (bilateral frontal sinus, right ethmoidal sinus), right orbit and anterior cranial fossa is reported in a Nigerian. Malignant schwannomas of the paranasal sinus are extremely rare, as only 20 well-documented cases have been previously published in English literature. No report in black Africans has been found in extant literature. The clinical features of this tumour are presented with detailed management. The patient had a wide surgical resection of the lesion with reconstruction of the resultant fronto-nasal defect using forehead musculofascial flap plus full thickness skin graft and adjuvant radiotherapy with satisfactory outcome. The good result of combined surgery and radiation regimens in this case demonstrates the usefulness of adjuvant radiation therapy in this condition.