To observe the effects of Qilong capsule on acute myocardial ischemia (AMI) in the anesthetized dogs. Methods: Thirty-six dogs were randomized into six groups (n＝6), model group, Herbesser (0.5 mg/kg) group, Compound Danshen tablet (0.24 tablet/kg) group, Qilong capsule 256, 128, 64 mg/kg group. Acute myocardial ischemia model were established by ligating left anterior descending coronary arteries (LAD) of dogs. Changes of ST segment were determined by epicardial electrocardiogram (ECG), and coronary blood flow (CBF) were measured by ultrasonic Doppler flow meter. Myocardial oxygen consumption was measured by automatic blood gas analyzer, and serum creatine kinase (CK) and lactate dehydrogenase (LDH) were observed by fully automatic biochemical analyzer. Myocardial infarct size was assessed by nitro blue tetrazolium (N-BT) staining. Results: Administration of Qilong capsule reduced the myocardial infarct area/left ventricle area significantly compared with model group. Administration of Qilong capsule improved the ECG performance of Σ-ST from 15 min~180 min after the administration, and decreased the area of acute myocardial ischemia (N-ST) from 15 min~180 min after the administration. Qilong capsule can also increase blood flow of coronary artery from 30 min to 45 min after the administration. Compared with model group, Qilong capsule decreased serum CK and LDH significantly. Qilong capsule had no significant influence on blood oxygenation content. Conclusion: Qilong capsule protects myocardium in canine experimental myocardial infarction models, probably through proving blood supply of the cardiac muscle.