Objective To investigate the diagnostic accuracies among laparoscopic ultrasonography (LUS), CT, MRCP and transabdominal ultrasonography in secondary choledocholithiasis, and to compare the procedural efficacy of LUS carried out by surgeons assisted by ultrasound physicians, and by surgeons alone. Methods Forty-two patients underwent laparoscopic transcystic common bile duct exploration (LTCBDE) in Beijing Luhe Hospital, Capital Medical University. All these patients underwent LUS examination. In 26 patients, LUS was carried out by surgeons alone while in 16 patients it was assisted by ultrasound physicians. The results of intraoperative choledochoscopy were used to verify the results in the two groups in scan time, and in its accuracies when compared with CT, MRCP and preoperative abdominal ultrasound. Results The accuracy of LUS was 92.9%, which was significantly better than that of CT (73.8%) and transabdominal ultrasonography (23.8%, P 0.05). Surgeons alone were faster than ultrasound physicians in performing LUS [(8.5±3.0) min vs (13.2±4.6) min, P 0.05). Conclusion LUS diagnosed common bile duct stones by surgeons who had adequate ultrasound training, with a high accuracy rate and good efficiency. Key words: Laparoscopic ultrasound; Secondary choledocholithiasis; Bile duct exploration