Background: Laparoscopic renal cyst decortication often uses three-port incisions or single-port incision with three or four channels (laparoendoscopic single-site surgery). This article introduces a modified laparoendoscopic single-site surgery for the treatment of simple renal cysts: single-channel retroperitoneal laparoscopic decortication (SCRL) of a simple renal cyst. Patients and Methods: From January 2008 to December 2011, either SCRL or standard three-port-incision retroperitoneal laparoscopic decortication (SRL) was performed for the treatment of a simple renal cyst. The SCRL procedure was as follows. The patients were placed in the lateral decubitus position. A 1.2-cm horizontal skin incision was made over the midaxillary line, 3 cm above the iliac crest. The retroperitoneum working space was established. A 10-mm operative laparoscope, which is similar to a nephroscope, was introduced into the retroperitoneum cavity through a 1.1-cm port. The cyst was exposed and then sutured to help to suspend the cyst wall so that the cyst could be decorticated easily. Perioperative and follow-up data from SCRL and SRL were collected retrospectively. Results: Based on the cyst location as the major selection criterion, 92 cases were enrolled for further analysis. Of these, 38 patients were treated with SCRL, and 54 patients were subjected to SRL. No SCRL was converted to SRL, and no SRL was converted to open surgery. The operation time and the drain tube removal time in these two approaches were similar (P > .05), but the average duration of hospital stay in the SCRL group was shorter (P = .02). Six months after the surgery, renal ultrasound results showed that the diameter of the cyst in these two groups also had no significant difference (P > .05). Conclusions: With appropriate selection of patients, the SCRL approach has the same efficacy with better cosmesis compared with SRL.