A 63-year-old man was referred to our hospital with a 3-year history of intermittent claudication, and his angiogram showed a total occlusion of the bilateral infrainguinal arteries. In addition, based on a platelet count of 172 x 10(4)/mm(3) as well as the characteristic bone marrow findings, he was diagnosed to have essential thrombocythemia. After the platelet count and aggregation response improved on administration of ranimustine and antiplatelet agents, infrainguinal bypass surgery was performed using the saphenous vein and prosthetic grafts. The bilateral grafts had been patent for 10 months postoperatively, but his discontinuance of medication caused an acute occlusion of the prosthetic graft. The graft was salvaged with a prompt thrombectomy and, now under strict medication control, he is leading an active life.