Objective To summarize selection of therapeutic method for isolated iliac aneurysms and analyze its advantages and disadvantages. Method The clinical data of 21 patients with isolated iliac aneurysms from January 2006 to January 2017 in this hospital were analyzed retrospectively. Results Four patients were treated with an open surgery such as the unilateral iliac prosthetic graft interposition, aorto-biiliac or aorto-bifemoral arterial bypass graft, ligation of internal iliac artery, etc.. Seventeen patients were treated with an endovascular treatment such as the unilateral iliac stent-grafts, bifurcated aortic stent-grafts, or coil embolization alone, etc.. One patient with ruptured isolated iliac aneurysms died during the endovascular repair, and the rest patients were cured after the operation. The average operative time was 2.83 h and 1.58 h, the average hospital stay was 17.5 d and 7.7 d respectively for the patients with the open surgery and the endovascular treatment. Except 1 case of type Ⅰ and 1 case of type Ⅱ endoleaks were found in the patients with the endovascular treatment, no complications such as the ureteral and intestinal injuries, the gluteal muscle claudication, and the sigmoid ischemia were found in all the patients. Seventeen cases were followed-up. The following-up rate was 85%. The following-up time was 1–60 months with an average of 22 months. During the following-up period, the grafts and stent grafts were patent and the aneurysm sac diameter was unchanged. The abscess of the iliac fossa occurred in 1 patient with systemic lupus erythematosus and improved after the symptomatic treatment. Two patients died of other diseases during the following-up period, and the rest had no obvious clinical symptoms. Conclusions Preliminary results of limited cases in this study show that endovascular repair and open surgery in treatment of appropriately selected patients with isolated iliac artery aneurysms is safe and effective. But in special situation, technical controllability of open surgery might be better than endovascular repair, treatment should be selected according to patient’s general condition and anatomy of aneurysm.