Meningioma is the most common type of benign intracranial tumor. The occurrence of extracranial meningioma is rare, accounting for only 2% of all meningiomas. There are two types of extracranial meningioma: primary and secondary. Primary extracranial meningioma grows extracranially without any connection to intracranial lesions, whereas secondary extracranial meningioma is an intracranial meningioma that extends extracranially. Herein, we report the case of a 45-year-old female patient with secondary extracranial sinonasal meningioma who presented with intermittent headache and unilateral proptosis due to olfactory groove meningioma that expanded to the right ethmoid sinus. Gross tumor resection was achieved in this case. © 2020 by Nova Science Publishers, Inc.