Objective: To investigate the prevention and treatment of endoleak by summarizing our experience of endovascular aneurysm repair. Methods: The clinical data of 43 patients with infrarenal abdominal aortic aneurysm undergoing endovascular repair (EVAR) from January 2007 to December 2012 in Qilu Hospital and Laiwu-Steel Company Hospital were analyzed retrospectively. The causes, prevention and treatment of endoleak were analyzed. Results: Pimary endoleak after intervention occurred in 11 patients, of whom, 8 cases were type I, 1 case was type II, and 2 cases were type III; 9 cases underwent bifurcated stent-graft implantation and 2 cases underwent tubular stent-graft implantation. The one type II endoleak was not treated because the leak was small; after first-stage balloon dilatation or stent-graft implantation 2 cases of type I endoleaks still existed, but all the other type I and III endoleaks were resolved. Thirty-nine patients were followed up. During the period of 4 to 50 months of follow-up, 2 delayed type Ib and 2 delayed type II endoleaks were found, but the aneurysms did not enlarge during the following 1- to 2-year follow-up period. The residual primary endoleak in 3 cases spontaneously disappeared, but type Ia endoleak recurred in 1 case 6 months after operation, which caused the aneurysm recurrence and rupture and a second endovascular repair. Conclusion: The occurrence of endoleak is related to anatomic condition, stent defects and surgical skill. Prevention and treatment of endoleaks require a good grasp of surgical indications, reasonable choice of stent, and mature operating experience.