Atrial fibrillation (AF) is one of the most common complications after cardiac surgery. The existing treatment of postoperative AF mainly focuses on preoperative prevention, intraoperative protection and postoperative treatment for factors prone to AF before, during and after surgery, but the postoperative treatment in various areas and hospitals is different. This article combines the latest literature published in Europace about the practice guidance of cardioversion of AF and atrial flutter, and summarizes the treatment of electrical cardioversion, in order to provide clinical guidance for electrical cardioversion of AF after cardiac surgery.