In recent years,the incidence of myocarditis has been increasing year by year.The clinical manifestations of patients vary greatly with common symptoms in infants and young children and atypical clinical manifestations in most adults.Patients with severe myocarditis may have serious concurrent symptoms,such as arrhythmia,cardiac insufficiency or even sudden death.Because of its lack of specificity in clinical manifestations and auxiliary examination results,and its insufficient understanding of pathogenesis,the diagnosis is difficult.Therefore,early diagnosis and treatment of patients with myocarditis is particularly important.This article reports on patients with myocarditis misdiagnosed as myocardial infarction,hoping to provide ideas for clinical diagnosis of myocarditis.