Muscle relaxants are the most common cause of anaphylaxis during anesthesia. An intradermal skin test is commonly used to investigate the cause of anaphylaxis. A 46-year-old man was scheduled for percutaneous nephrolithotripsy. He had a history of a positive intradermal skin test to muscle relaxants for general anesthesia. After injection of thiopental sodium, anesthesia was induced, which gradually deepened with increments of sevoflurane in 100% oxygen. Tracheal intubation was performed smoothly, without adjunct muscle relaxant. After stabilization, a small dose of vecuronium was administered, but the blood pressure transiently decreased, and the oxygen saturation was decreased from 98 to 92% for 30 minutes. No muscle relaxant was used thereafter, and the anesthesia was maintained with sevoflurane, nitrous oxide and oxygen with intermittent propofol administration. Surgery was completed uneventfully, and the patient recovered without any adverse reaction. To prevent anaphylaxis, the use of a suspicious causative agent should be avoided.