Near-infrared spectroscopy (NIRS) can be applied to monitor regional cerebral oxygen saturation(rSO2) in a noninvasive, real time and continuous manner, providing information about the equilibrium between cerebral oxygen supply and consumption in regional cerebral tissues and indirectly reflecting cerebral blood flow. This technique was initially adopted in cardiac surgery and neonatal intensive care units. It shows better sensitivity and specificity than conventional indicators, and is consequently more beneficial to guarantee patient cerebral function during perioperative period and reduce the incidence of postoperative complications. This article reviews NIRS monitoring principle, limits, recent progress in perioperative application and future development, so as to promote its use in high-risk populations in perioperative period, reduce nerve system complication after anesthesia in surgery and improve prognosis.