Objective: To evaluate the efficacys of myocardial protection by wann blood cardioplegia (WBCP) compared with crystalloid cardioplegia (CCP) in patients undergoing congenital cardial surgery. Subjects and method: Prospective study of experimental clinical control from December 2010 to March 2012. There were 79 patients undergoing atrial septal defect and ventricular septal defect surgery were divided into two groups, 36 patients were randomly allocated WBCP and 43 patients served as CCP. Results: Base on our data, the efficacys of wann blood cardioplegia were better crystalloid cardioplegia. The lactate concentration in coronary sinus was significantly lower after wann blood than cryfalloid cardioplegia (6.3 mmol/L vs 8.7 mmol/L, p 0.001), and troponin I release also significantly diffeffent between groups (2.9 ng/ml vs 3.7 ng/ml, p