The authors describe a case of pseudoaneurysm arising from internal iliac artery presented with radiculopathy mimicking the symptoms of lumbar disc disease or spinal cord tumor. Among the several preoperative evaluation including CT, MRI, electrophysiologic study and ultrasonography, important diagnostic clue was obtained by ultrasonographic findings of turbulence flow at the core of partially enhanced mass in the pelvic cavity. The patient was managed with endovascular coil embolization successfully. The current case makes us remind that assessment of neurological symptoms on lower extremity should include consideration of extraspinal cause in pelvis.