Common cardiovascular surgeries include coronary artery bypass grafting, cardiac valve replacement, radiofrequency ablation, and cardiac intervention surgery. Multiple postoperative complications, such as hypoxic encephalopathy, air embolism, retained intracardiac air, cognitive dysfunction and major adverse cardiovascular events, including heart failure, ischemic stroke, and myocardial infarction, may occur after these cardiovascular surgeries. Hyperbaric oxygen can be used in preconditioning to lower the morbidity of adverse complications. It is also effective for the treatment of numerous postoperative complications. We provide evidence from the current literature highlighting the use of hyperbaric oxygen therapy for preconditioning and managing postoperative complications.