Aneurysms of lenticulostriate artery (LSA) have rarely been reported. We present an extremely rare case of bilateral aneurysm of LSA, which spontaneously disappeared. A 59-year-old man presented to us with a decreased level of consciousness. Twice repeated blood culture was negative. Computed tomography (CT) showed bilateral basal ganglia hemorrhage with intraventricular extension and acute hydrocephalus. We performed external ventricular drainage. Cerebral angiograms, on 3 days after the onset, disclosed two aneurysms on the left LSA and one aneurysm on the right LSA. Cerebral angiography after 9 weeks demonstrated complete disappearance of three aneurysms.