BACKGROUND: Even though lasers have been used in hemorrhoidectomies, there has been much debate about their effect. PURPOSE: A prospective randomized study was performed comparing the efficacy of a Nd:YAG laser with that of scalpel excision when performing a ligation excision, semi-closed hemorrhoidectomy. METHODS: Sixty patients, who had more than three piles, with 3rd or 4th grade hemorrhoids, were enrolled into this study. Hemorrhoidectomies were performed under low spinal anesthesia. The ligation excision, semi-closed hemorrhoidectomy technique was used. Data evaluated included age, sex, operative time, postoperative pain scores, postoperative analgesic requirement, wound-healing time, and postoperative complications. Of the sixty patients enrolled into this study, 30 received laser excision and the other 30 scalpel excision. RESULTS: There were no significant differences between the two groups, except for operative time (laser, 34.6 8.4 min; scalpel, 24.1 4.8 min). Postoperative complications, such as urinary retention, fecal impaction, skin tags, and postoperative fissure, were more common in the laser group. CONCLUSIONS: A hemorrhoidectomy using a Nd:YAG laser takes longer than a conventional hemorrhoidectomy and neither reduces the postoperative pain nor shortens the wound-healing time. For achieving an effective treatment in hemorrhoids by using lasers, improved laser instruments are required, along with more detailed study of lasers and their effects.