OBJECTIVE To investigate the therapeutic effects of Ginkgo biloba extract (EGb) in rats with acute myocardial injury induced by isoproterenol (ISO). METHODS The rats, induced by Isoproterenol (4 mg x kg(-1) x d(-1), 10 d, sc), were divided into groups: sham, model, metoprolol (10 mg x kg(-1) x d(-1), 13 d, ig), EGb (100 mg x kg(-1) x d(-1), 13 d, ig). RESULTS The cardiac parameters of the Model group were compromised significantly in both systolic and diastolic function. Improvement in cardiac function by EGb was significant. In model groups, plasma activities of AST, LDH, CK, HBDH, CKMB and ventricular weight index (LV and RV/BW) were elevated significantly. With the treatment with EGb and metoprolol, the enzymes and ventricular weight index were significantly ameliorated. CONCLUSIONS G. biloba extract was beneficial to cardiac performance by improving myocardium enzymes and cardiac function in isoproterenol induced myocardial injury in rats.