The relationships between temperature indices and clinical condition on admission or improvement after ventriculoperitoneal (VP) shunting were evaluated in patients with subarachnoid hemorrhage (SAH). Brain temperatures were measured at intervals of 1 cm from the brain surface to the lateral ventricle at shunt operation. Rectal temperature was also measured. The difference between intraventricular and rectal temperatures was correlated with age (p ＝ 0.0486), Glasgow Coma Scale (p ＝ 0.0129), Hunt and Hess grade (p ＝ 0.0101), and improvement score after VP shunting (p ＝ 0.0104). Measurement of brain temperature may predict the outcome of VP shunting in patients with SAH.