Chest pain has been associated with electrocardiographic ST-T changes and elevated levels of myocardial damage markers. It may be induced by acute coronary syndrome, myocarditis, stress cardiomyopathy, acute pericarditis, pulmonary embolisms, and cerebrocardiac syndrome. Few studies have evaluated chest pain accompanied by electrocardiographic ST-T changes and elevated myocardial damage markers during subacute thyroiditis. The present study describes a 19-year-old man with subacute thyroiditis combined with myocardial damage, exploring the mechanisms of this condition.