Single incision laparoscopic surgery(SILS) has offered significant advantages to patients, including nearly scarless wounds and reduced wound morbidity . In the same time, it has also increased the burden on surgeons because the entire operation is performed solely through one small incision. Accordingly, SILS is usually limited to operations in which the procedure is uncomplicated or less technically demanding. Common bile duct exploration (CBDE) is a complicated surgery that includes a series of steps such as choledochoscopic lithotripsy and common bile duct (CBD) repair. Hence, reports on single-incision laparoscopic (SIL) CBDE are limited. Recent advances in techniques and instruments have led to a progression of laparoscopic CBDE procedure. Moreover, current trends of no T-tube implementation during CBDE have further simplified the pocedure. Thus, these changes have opened wide the way for SIL-CBDE. Here, we describe needlescopic grasper-assisted single-incision CBDE (nSIL-CBDE). This technique is a modification of SIL-CBDE in order to reproduce the environment of laparoscopic CBDE by the addition of a very fine (2-mm) needlescopic grasper apart from the umbilical port. Simple addition of the needlescopic grasper to SIL-CBDE was expected to simultaneously enhance operative proficiency and minimize wound trauma. nSIL-CBDE is more efficient to closure CBD opening site by comparing with those of conventional laparoscopic CBDE (CL-CBDE). We can use an EHL(Electrohydraulic lithotripsy) to destroy an impacted CBD stone in nSIL-CBDE. In this study, we aimed to demonstrate the safety and operative feasibility of nSIL- CBDE by comparing the surgical outcomes of nSIL-CBDE with those of conventional laparoscopic CBDE (CL-CBDE) using special devices.