Abstract: Objective: To summarizing our experience of performing cardiopulmonary bypass （CPB） for coronary artery bypass graft （CABG）. Methods: Retrospective analysis of 243 on-pump CABG in our hospital from January 1997 to December 2000. Four cohorts were examed 1997（n=27）, 1998（n=46）, 1999（n=81） and 2000（n=89）. Age range was 20-75 years （mean 57.59 years）. Stock-Ⅲ type of heart-lung machine, membrane oxygenator, arterial annula（22-24F） and tow-stage atrium caval cannula （34/48Fr） were used in all patients. Cardioplegia with blood 4:1 was perfused discontinuously or continuously. To compare the 4 groups in clinical data. Results: There were not significantly different among groups about clinical data （P＞0.1）. Compared with 1997, the ischaemic time was shortened （P＜0.01）, the lowest nasopharynx temperature during CPB was raised （P＜0.01）, the hemodilution was decreased （P＜0.01） and the duration of postoperative respirator ventilation and ICU were shortened （P＜0.05） in the other groups. One （0.41%）case died from allergic shock of promine. Conclusion: The on-pump for CABG has improved march in our hospital. On-pump CABG is a safe, effective method especially to those severely ill patients.