Atrial fibrillation is the most common clinical arrhythmia, referred to as atrial fibrillation. Atrial fibrillation is very dangerous, and the main common hazards are atrial fibrillation of heart disease such as heart failure and embolism of the body circulation, especially cerebral embolism. The incidence of cerebral embolism in patients with atrial fibrillation is about five times higher than in those with non-atrial fibrillation. Many patients with atrial fibrillation are clinically diagnosed with cerebral embolism. Therefore, once a patient is diagnosed with atrial fibrillation, he or she should receive treatment at the hospital in a timely manner, regardless of whether he or she has symptoms. So what principles should be followed in the treatment of atrial fibrillation? The principles of atrial fibrillation treatment are to restore and maintain sinus rhythm, control the ventricular rate, and prevent thromboembolic complications. First, for all patients with atrial fibrillation, restoration of sinus rhythm is the best treatment option for atrial fibrillation. For patients with permanent atrial fibrillation, if the left atrial internal diameter is too large and cannot be converted to sinus rhythm due to the long duration of the disease, ventricular rate control and medication to slow down the fast ventricular rate are needed to reduce the occurrence of heart failure due to the long-term fast heart rate. For patients with atrial fibrillation who cannot be converted to sinus rhythm, in order to prevent thromboembolic complications in patients with atrial fibrillation, anticoagulant drugs should be selected according to the patient’s condition and the risk of thromboembolism to prevent embolism in the body circulation, especially cerebral embolism.