A rare case of crural arterio-venous fistulae due to orthopedic surgery was presented. A 60-year-old female patient received a corrective fibulotomy just below the fibular head under the diagnosis of osteoarthropathy of the left knee joint 3 years ago. Intractable pain and swelling of the left leg appeared shortly after operation, probably due to deep vein thrombosis. A faint thrill on the left saphenous vein afforded a clue for detecting a co-existing arterio-venous fistula. Confirmative cine-angiography revealed a few a-v-fistulae at the level of crural trifurcation, which might have exacerbated the symptoms of deep vein thrombosis. On entering the trifurcation, which was embedded in scar tissues, there were two a-v-fistulae, originating separately from the peroneal artery and the posterior tibial artery. These fistulae were closed directly, one from the peroneal artery through the lateral approach resecting the upper one third of the fibula, and the other from the posterior tibial artery through the standard medial approach. Postoperative course was uneventful, and the swollen leg subsided rapidly with remarkable improvement of symptoms such as pain, dullness, night cramp of the calf and etc. Concerning to the medical literature on iatrogenic arterio-venous fistula due to orthopedic surgery, no similar case has been reported at least in these ten years on crural arterio-venous fistula after corrective fibulotomy.