PURPOSE: Nonoperative management followed by an interval appendectomy is a commonly used approach for treating patients with perforated appendicitis with abscess formation. As minimally-invasive surgery has developed, single-port laparoscopic surgery (SPLS) is increasingly being used to treat many conditions. We report our initial experience with this procedure using a multichannel single-port. METHODS: The study included 25 adults who underwent a single-port laparoscopic interval appendectomy for perforated appendicitis with periappendiceal abscess by using a single-port with or without needlescopic grasper between June 2014 and January 2016. RESULTS: Of the 25 patients, 9 (36%) required percutaneous drainage for a median of 7 days (5-14 days) after insertion, and 3 (12%) required conversion to reduced-port laparoscopic surgery with a 5-mm port insertion because of severe adhesions to adjacent organs. Of 22 patients undergoing SPLS, 13 underwent pure SPLS (52.0%) whereas 9 patients underwent SPLS with a 2-mm needle instrument (36.0%). Median operation time was 70 minutes (30-155 minutes), and a drainage tube was placed in 9 patients (36.0%). Median total length of incision was 2.5 cm (2.0-3.0 cm), and median time to soft diet initiation and length of stay in the hospital were 2 days (0-5 days) and 3 days (1-7 days), respectively. Two patients (8.0%) developed postoperative complications: 1 wound site bleeding and 1 surgical site infection. CONCLUSION: Conservative management followed by a single-port laparoscopic interval appendectomy using a multichannel single-port appears feasible and safe for treating patients with acute perforated appendicitis with periappendiceal abscess.