Abstract Background Internal iliac artery (IIA) preservation continues to be a challenge during open surgery or endovascular repair of abdominal aortoiliac aneurysm (AAIA). Objectives To determine the results in terms of survival and clinical outcomes in patients with aortoiliac aneurysms (AAIA) treated with endovascular (EV) or open surgical (OS) repair. Methods This was a retrospective consecutive cohort study of patients with AAIA who underwent EV or OS repair. Results Post-procedure hospitalization time and intensive care unit stay were both longer in the OS group than in the EV group (7.08 ± 3.5 days vs. 3.32 ± 2.3 days; p = 0.03; 3.35 ± 2.2 days vs. 1.2 ± 0.8 days; p = 0.02, respectively). There were two cases of bowel ischemia (4.7%; OS 8.3% and EV 3.2%; p = 0.48), two cases of buttock claudication (4.7%; OS 8.3% and EV 3.2%; p = 0.48), and one case of sexual dysfunction (2.3% OS), all of them in patients with bilateral occlusion of the internal iliac artery (five patients, 11.6%; p = 0.035). Overall survival at 720 days was 80.6% in the EV group and 66.7% in the OS group (p = 0.58). Conclusions In the present study, OS and EV repair of aortoiliac aneurysms had similar overall survival and outcomes. Preservation of at least one internal iliac artery is associated with good results and no further complications.