A patient who received two kidney transplants was placed on hemodialysis after failure of both grafts. He had complained of abdominal pain during the preceding month and was found to have a pulsating mass in his right pelvic region. Computed tomography and color Doppler studies showed a large pseudoaneurysm of the common iliac artery. We describe the treatment of this lesion by the use of ultrasound-guided thrombin injection. To the best of our knowledge, this is the first report regarding the use of ultrasound-guided percutaneous thrombin injection for treatment of such a pseudoaneurysm.