Complete recanalization was achieved by intra-aortic infusion of urokinase in a case of complete occlusion of the abdominal aorta. The patient was a fifty-nine-year-old man with atrial fibrillation, hypertension, and diabetes mellitus who was admitted because of intermittent claudication and pain in both lower extremities at rest. Angiography demonstrated complete obstruction of the abdominal aorta, but the bilateral iliac arteries were visualized via collaterals. Urokinase was administered intra-aortically in a total dose of 1,200,000 U during the first day and a total dose of 960,000 U during the second day. The aorta and the iliac arteries recanalized after this treatment, and complete recanalization associated with disappearance of subjective symptoms was observed after one month of treatment with warfarin. The present case suggests the usefulness of intra-arterial infusion of urokinase for the treatment of complete occlusion of the abdominal aorta.