In this report, we describe the use of new small-diameter forceps (Endo Relief forceps) for port-reduced thoracoscopic surgery. Forceps were designed with end that were the same size and shape as conventional 5-mm forceps, except that the diameter of the shaft was decreased to 2.4 mm. Endo Relief forceps were used for thoracoscopic surgery in 18 patients. We retrospectively compared the frequency of grasping error between conventional small-diameter forceps and Endo Relief group. The mean surgical time was 57.5 minutes (range, 45–75 minutes). There were no complications, no recurrences of pneumothorax and lung cancer, and no deaths after surgery. There were no intraoperative complications and no need for a second surgery to open additional ports. The frequency of grasping error was significantly lower in the Endo Relief group compared to the conventional small-diameter forceps group (0.17 ± 0.23 vs 1.33 ± 0.22; P = 0.022). Our experience thus far indicates that this technique has cosmetic benefit and is as effective as the classic 3-port technique for experienced thoracoscopic surgeons. Endo Relief forceps has a safety comparing conventional small-diameter forceps.