Up to 100% of patients treated with epidural analgesia can experience urinary retention, which may be related to dermatomal level of the epidural block, epidural medication, and surgical procedure. This study was designed to identify the incidence of urinary retention in patients who receive thoracic patient-controlled epidural analgesia (TPCEA) after thoracotomy. Forty-nine patients were enrolled and received epidural infusion of ropivacaine 0.2% or mixture of bupivacaine 0.1% with hydromorphone 0.015 mg/mL. Epidural catheter placement level was verified by chest X-rays. Indwelling urinary catheters were removed between 12 and 48 h after surgery when no longer required for fluid monitoring. Four hours later, patients were assessed for urinary retention using bladder ultrasound. Residual bladder volume was recorded, and urinary retention was defined as an inability to void or a bladder volume of greater than 600 mL at 4 h. Twenty-four hours after the catheter removal, patients completed a questionnaire to assess their perception of the indwelling catheter before and after its removal. Five participants (˜10%) with epidural catheters between T3 and T5 with bupivacaine/hydromorphone epidural solution were recatheterized. No association was established between catheter level, drug type, infusion rate, and urinary retention. Although 76% of patients did not report any physical discomfort with the indwelling urinary catheter, 66% felt relief after its removal and 18% did not ambulate with the inserted urinary catheter. The incidence of postoperative urine retention was low (10%), indicating that unless required for other purposes, indwelling urinary catheters may be removed between 12 and 48 h after surgery while receiving TPCEA.