Meningiomas, thought to arise from arachnoid cap cells, are usually attached to the dura. Malignancy is present in approximately 1% of these tumors. The authors report the case of a patient with a malignant meningioma arising from the oculomotor nerve with no dural attachment. The patient presented with a 7-month history of left-sided ptosis and diplopia. Magnetic resonance imaging demonstrated an extrinsic mass compressing the root of the oculomotor nerve at its exit from the midbrain. During surgery, a left-sided subtemporal approach revealed the tumor to be arising from the oculomotor nerve. Histological investigation showed a malignant spindle cell lesion with an immunohistochemical profile that was consistent with malignant meningioma. To the authors' knowledge, this is the first documented case of a malignant meningioma arising from the oculomotor nerve.