The sciatic artery is a major artery of the lower limb during the early embryonic period, which involutes at the third month of embryonic life. The persistent sciatic artery (PSA) is a rare congenital anomaly, which may predispose a subject to atherosclerotic or aneurysmal degeneration. They usually present with leg ischemia or a throbbing buttock mass, but infrequently with a sciatic nerve compression symptom. We report a 56 year- old woman with PSA, who presented with back pain and a sciatic nerve compression symptom, which was erroneously diagnosed as spinal cord compression due to spinal stenosis. She was successfully treated with an above knee femoropopliteal bypass, with a reversed saphenous vein and surgical exclusion of the sciatic artery.