A 50 year-old woman was scheduled for clipping of giant middle cerebral artery (MCA) aneurysm. Preoperative four-vessel angiography and computed tomography scan revealed a giant aneurysm (3.5x3.3x3.5 cm) at bifurcation of right MCA. Induced hypotension and brain protection using sodium nitroprusside (SNP) and thiopental loading were planned to prevent cerebral damage during the operation. Before induction, esmolol, lidocaine and vecuronium were administered. Mask ventilation with isoflurane in N2O and O2 was performed over 5 minutes and then tracheal intubation was done. Anesthesia was maintained by isoflurane+N2O+O2 with pancuronium. Electrocardiography, pulse oxymetry, capnography, central venous pressure, evoked potential and invasive arterial blood pressure were monitored. She was hyperventilated intraoperatively with a PaCO2 around 30 mmHg. Perioperative hypotension was achieved with infusion of SNP (0.3~1.0 microg/kg/min). During the actual aneurysm surgery, mean arterial pressure was lowered to approximately 50 mmHg. Adjuvant drugs such as methylprednisolone, mannitol and furosemide to reduce intracranial pressure were also administered. This technique established good brain conditions during clipping of the aneurysm. A thiopental loading (4 mg/kg) was supplied while the aneurysm was approached. Satisfactory and well-controlled hypotension was obtained after thiopental and SNP. Postoperatively, the patient was transferred to the intensive care unit.