To our knowledge, this review will be the first to analyze literature on the general incidence of MH. Although the most common initial signs of MH, such as hypercarbia, sinus tachycardia, masseter spasm, and elevated body temperature, become evident soon after anesthetic administration, we may not recognize these as early signs of MH in the absence of musculoskeletal disorders, family history of MH, and known genetic abnormalities. The main reason for conducting this systemic review and meta-analysis is to provide better insight into this fatal but clinically important complication. Overall, we believe that our systematic review will provide new information on the incidence of MH in patients undergoing general anesthesia.