Abstract: Objective: To investigate the change characteristics of ST segment elevation in patients with myocardial infarction during hyperacute period.Methods: The clinical data of 10 patients with myocardial infarction were retrospectively analyzed,and the patients were divided into the death group and improvement group according to the prognosis(5 cases each group).The examination results of electrocardiogram and serum marker between two groups were compared.Results: The "tombstone type" ST segment elevation in 3 cases and "giant R-wave type" ST segment elevation in 2 cases in death group were found,the "plagioclase type" in 1 case, "crescent type" in 2 cases,"horizontal type" in 1 case and "arched type" in 1 case in improvement group were identified,and the difference of which between two groups was statistical significance(P<0.01).The myocardial enzyme in two groups changed after 5 h of the onset,and the difference of the levels of CK-MB and cTnT between two groups were not statistical significance(P>0.05).Conclusions: The ST segment elevation phenomenon is found in most patients with acute myocardial infarction,the "tombstone type" and "giant R-wave type" ST segment elevation maybe the serious manifestations of cardiac injury,the mortality of patient is high.