Background: The association of moyamoya disease and posterior cerebral artery aneurysms is relatively rare and the prognosis is poor. The management is extremely challenging for neurosurgeons.

Case Report: We report a case of a 58-year-old man with a history of moyamoya disease who admitted complaining of sudden-onset headaches, vomiting, and seizure and the investigations revealed a subarachnoid hemorrhage, intracerebral hematoma, posterior cerebral artery aneurysms on a moyamoya disease field. The patient was treated surgically by the clipping of the aneurysm, but developed three days later a complication of the MMD and died.

Conclusion: The prognosis of this association is very poor, explain the fact that a therapeutic strategy should be done to reduce the mortality and to determine the best management which is surgery versus embolization and revascularization.