Antithrombotic therapy, including antiplatelets and anticoagulation, is highly effective for prevention of thrombotic complications in patients with coronary artery disease or atrial fibrillation. However, antithrombotic therapy usually induces bleeding. As for the elderly patients, they usually suffer from multiple organ diseases and the risk of thrombosis and bleeding are both significantly increased. It is very important to choose the most beneficial antithrombotic regimen based on the balance of risk of thrombosis and bleeding.