Malignant hyperthermia (MH) is an extremely rare and life-threatening differential diagnosis of postoperative fever. We present an 8-month-old child scheduled for elective outpatient procedure who rapidly developed high fever, tachycardia, and respiratory acidosis shortly after transfer to the postanesthesia care unit. MH hotline expert recommended administering dantrolene, but there was no evidence of hypermetabolism or lactic acidosis. The patient remained clinically stable after admission to the pediatric intensive care unit and was discharged home the next day. The fever was likely due to viral infections as confirmed by a positive result of viral polymerase chain reaction for human metapneumovirus and rhinovirus/enterovirus.