Atrial fibrillation (AF) is the most common arrhythmia after coronary artery bypass grafting (CABG). AF is a vexing problem that causes morbidity, prolongs hospital stay, and increases costs. Numerous factors have been suggested to play a role in the development of AF. The aim of this study was to evaluate the effect of intermittent aortic cross clamping (IACC) compared with hypothermic cardioplegic solution (HCS) in the development of postoperative AF. We evaluated data obtained from 345 patients undergoing CABG with HCS (HCS group, n = 212) and IACC (IACC group, n = 173) between April 2004 and August 2005. Diabetes mellitus was observed more often in the HCS group (P < .05), otherwise both groups had similar preoperative characteristics including sex, age, the number of distal anastomoses, left ventricle ejection fraction, history of myocardial infarction, and use of beta-blocker medication. The only statistically significant difference between the groups was higher postoperative Ca-antagonist use in the HCS group. Rates of postoperative AF, however, were significantly lower in the IACC group (21.52%) than that in the HCS group (11.05%; P < .01). Postoperative Ca-antagonist use in the HCS group and smoking in the IACC group were independent predictors of AF after CABG. The incidence of postoperative AF after CABG with IACC was reduced compared with HCS. IACC with ventricular fibrillation may exert a counteractive effect against AF.