An 81-year-old woman was transferred to our hospital after suffering loss of consciousness. Computed tomography revealed subarachnoid hemorrhage. Angiography revealed middle cerebral artery fenestration and a ruptured aneurysm arising from the inferior limb of the fenestrated artery. Coil embolization of the aneurysm and the proximal portion of the inferior limb was performed, and she showed good recovery after the procedure. Ruptured aneurysms associated with middle cerebral artery fenestration are very rare, but may occasionally have complex structures that complicate lesion treatment, so coil embolization should be considered in some cases.