Aim To evaluate the protective effect of anti_digoxin antiserum on hypoxic injury myocardium and its mechanism. Methods It was observed that different concentration anti_digoxin antiserum effect on endogenous digitalis_like factor and cell membrane ATPase activity in hypoxic myocardium model. Results The level of endogenous digitalis_like factor was remarkably higher, cell membrane ATPase activity were remarkably lower in hypoxic group than those of normal group; anti_digoxin antiserum can resume membrane ATPase activity.Conclusion Rise of endogenous digitalis_like factor was basic of molecular biology of myocardial damage during myocardial hypoxia. Anti_digoxin antiserum has lightened myocardial injury and has protective effect on hypoxic myocardium by against effect of endogenous digitalis_like factor.