A five year-old boy undergoing elective tonsillectomy sustained cardiac arrest following the administration of a single dose of succinylcholine during induction of anesthesia. With a 10-minute cardiopulmonary resuscitation (CPR) during which intravenous calcium gluconate, epinephrine, and sodium bicarbonate were given and DC counter shock applied, we were successful to restore cardiac activity without neurological sequelae. The cause of cardiac arrest we speculated was hyperkalemia, possibly secondary to succinylcholine-induced rhabdomyolysis. It is suggested that succinylcholine should not be used in patients with known or suspected muscular dystrophy.