History and Objective: Malignant hyperthermia (MH) is a rare and life-threatening complication that can occur at any time during general anesthesia or immediately after in susceptible patients exposed to anesthetic agents such as inhalational anesthetics and depolarizing muscle relaxants.Patient Introduction: A 19-year-old male was admitted for surgery due to a proximal humerus fracture. After the induction of anesthesia, he exhibited signs of increased end-tidal CO2 and elevated body temperature. Suspecting malignant hyperthermia following the administration of isoflurane, the anesthetic was discontinued, and the surgery was halted. Cold intravenous fluids were administered to reduce his temperature, and dantrolene was injected. Notably, a relative of his had previously experienced this disorder during anesthesia, resulting in death.Conclusion: There is a critical need for enhanced emphasis on obtaining accurate patient histories and raising awareness regarding necessary actions in such situations.