Since Cox-maze procedure was first reported in 1987, ablation technology has made great progress and revolutionized atrial fibrillation surgery. Various energy sources have been introduced to facilitate creating conduction block within the atria. These sources include radiofrequency, cryothermia, microwave, laser, and high-frequency focused ultrasound( HIFU). They have been utilized both endocardially in the arrested heart and epicardially in the beating heart. The goal of all these sources is to create transmural lesions which enable irreversible conduction block. They have been reported to have clinical efficacy, but each of them have their own advantages and disadvantages, and their ability of creating transmural lesions are also different. It is important for surgeons that they fully understand these differences to make appropriate use of these technologies for achieving safe atrial fibrillation surgery and developing less invasive new procedures.