Abstract: New-onset atrial fibrillation after cardiac surgery (NOPOAF) occurs in patients with normal rhythm before surgery and suffered transient or continuous atrial fibrillation after cardiac surgery during hospitalization. It is the most common adverse event in adults after cardiac surgery which causes high mortality, stroke rates, longer hospital stay time and additional treatment expenses. However, the underlying mechanisms and risk factors of NOPOAF still needs further research. It is of great interest to stratify patients into different risk categories, apply drug prophylaxis and improve surgical approaches. This review provides an up-to-date summary of pathogenesis, risk prediction and preventing strategies of NOPOAF, attempting to provide reference for further clinic work.