Purpose: To determine the influence of the abdominal aortic aneurysm (AAA) anatomy on the clinical outcomes after endovascular AAA repair (EVAR). Methods: Between January 2008 and December 2010, 53 patients underwent EVAR. The parameters outside of the device instructions for use (IFU) were: short neck length (<15 mm), proximal neck angulation (>60 degrees), small diameter of external iliac artery (<7 mm) and bilateral internal iliac embolization. Results: A total of 37% of these grafts were placed outside of at least one IFU parameter. The intraoperative problems encountered included one (3%) acute graft limb thrombosis, and one (3%) access vessel rupture within the IFU (w-IFU) group. One perioperative mortal case was observed in the w-IFU group due to thoracic aortic dissection. After one year follow-up, type II endoleak (EL) was recognized in 8 of 28 (29%) patients in the w-IFU group, and in 2 of 12 (17%) patients outside of the IFU (o-IFU) group. There was also no significant difference of early and mid-term outcomes between favorable neck anatomy and hostile neck anatomy (HNA). Conclusion: In our series, EVAR provided acceptable results even in the o-IFU group and HNA. This suggests that the IFU can be extended to other selected patients.