The authors assessed the relationship between cause of death and treatment modality in patients with peripheral arterial occlusive disease. A total of 273 patients were treated with percutaneous transluminal angioplasty, surgical reconstruction, amputation, or medical therapy. We evaluated the outcome in various patient subgroups divided by treatments with a mean follow-up of 4.9 years. Most patients died because of cardiovascular or cerebrovascular events, and cancer was the second most frequent cause of death. Furthermore, there was a significant difference in cancer deaths between patients who received prosthetic vascular grafts and those with other types of treatment (9.3% vs. 2.8%, p<0.01, odds ratio = 3.34). It is noteworthy that patients with peripheral arterial occlusive disease succumbed to cancer, especially the patients with prosthetic vascular grafts.