Myocarditis is still facing challenges clinically because of its complex pathogenesis and poor prognosis. Evidence shows that programmed cell death protein-1 (PD-1) is an important immunological checkpoint, and its binding to programmed cell death ligand-1 (PD-L1) can negatively regulate the immune response of the body and play an important role in the occurrence and development of myocarditis. This article reviews the roles of PD-1/PD-L1 in the pathogenesis of myocarditis in aspects of their regulation of T lymphocyte activation and inhibition of troponin antibody and myocardial inflammation in order to find a new target for the effective diagnosis and treatment of myocarditis.