Infected aneurysm of the abdominal artery has been found occasionally, but being accompanied with arteriovenous fistula detected by CT angiography has rarely been reported. A preoperative clinical diagnosis of infected aneurysm and arteriovenous fistula is difficult. We report a case of infected aneurysm of right common iliac artery, with the complication of arteriovenous fistula, causing thrombosis of the bilateral iliac veins and inferior vena cava. This case showed the periarterial abscess extension with partial thrombosis of iliac veins and inferior vena cava, which was not mentioned before in the literature. A contrastenhanced 64-row multiple detector CT scan with three-dimensional CT angiography is an effective, non-invasive method to detect the presence of aneurysm and its associated complications.