Congenital insensitivity to pain with anhidrosis (CIPA) is a rare, autosomal-recessive disorder characterized by the clinical triad of indifference of pain, anhidrosis and heat intolerance.Because of their lack of autonomic response to noxious stimuli, the determination of adequate depth of anesthesia in the CIPA patient undergoing surgery is a major challenge.We experienced a patient with CIPA who had minor procedures three times under the general anesthesia, in which bispectral index (BIS) was maintained at 40?50 by adjusting sevoflurane concentrations with 50% nitrous oxide.The low end-tidal sevoflurane concentrations (＜1.2 vol%) were required to keep the target BIS while vital signs remained stable throughout the surgery in each operation.BIS monitor may be a valuable tool to guide the depth of anesthesia in patients with CIPA.