Abstract-Venous thromboembolism (VTE) is a common complication of surgical procedures. The risk for VTE in surgical patients is determined by the combination of individual predisposing factors and the specific type of surgery. Prophylaxis with mechanical and pharmacological methods has been shown to be effective and safe in most types of surgery and should be routinely implemented. For patients undergoing general, gynecologic, vascular, and major urologic surgery, low-dose unfractionated heparin or low-molecular-weight heparin (LMWH) are the options of choice. For low-risk urologic surgery, early postoperative mobilization of patients is the only intervention warranted. For higher-risk patients, including those undergoing elective hip or knee replacement and surgery for hip fracture, vitamin K antagonists, LMWH, or fondaparinux are recommended. For patients undergoing neurosurgery, graduated elastic stockings are effective and safe and may be combined with LMWH to further reduce the risk of VTE. The role of prophylaxis is less defined in patients undergoing elective spine surgery, as well as laparoscopic and arthroscopic surgery. A number of issues related to prophylaxis of VTE after surgery deserve further clarification, including the role of screening for asymptomatic deep vein thrombosis, the best timing for initiation of pharmacological prophylaxis, and the optimal duration of prophylaxis in high-risk patients. Key Words: venous thromboembolism Ⅲ deep vein thrombosis Ⅲ pulmonary embolism Ⅲ heparin Ⅲ low-molecular-weight heparin Ⅲ vitamin K antagonists