Objective：To study the relative factors of type Ⅱ endoleak after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms. Methods: Twenty-eight cases of abdominal aortic aneurysms treated by EVAR were retrospectively analyzed. The characteristics of the inferior mesentery arteries (IMA), the arc Riolan and the lumbar arteries of the cases with or without type Ⅱ endoleak were analyzed. Results: Type Ⅱ endoleak was found in 8 (28.6%) cases, of which, 2 were type Ⅱa and 6 were type Ⅱb. The diameter of the IMA originating part of the cases with type Ⅱ endoleak ［(4.03±1.00) mm］ was significantly bigger than that without endoleak ［(2.89±0.50) mm, P=0.007］. The number of the lumbar arteries originating from the aneurysm sac in cases with type Ⅱ endoleak (3.4±0.8) was significantly more than that without endoleak (1.9±1.5, P=0.017). However, type Ⅱ endoleak was irrelevant to the diameter of originating part of the lumbar arteries and the form of the arc Riolan. After the average 14.5 months follow-up, the aneurysm sac was found with shrinkage in 1 case, no change in 2 cases, and augment in 5 cases. Secondary transarterial embolization was performed for only 1 case. Conclusion: Type Ⅱ endoleak was much easily found in cases with bigger diameter of originating part of the IMA, or in cases with more lumbar arteries originating from the aneurysm sac.