INTRODUCTION: It has been estimated that 58% of people over 40 years of age have haemorrhoidal disease to some extent. Indications for operative treatment include third and fourth degree prolapsing haemorrhoids. Haemorrhoidectomy is frequently associated with significant postoperative pain and new techniques to reduce this pain are constantly under evaluation. The present study was conducted to determine the usefulness of the Ligasure system and compare it with conventional diathermy for haemorrhoidectomy. METHODS: 25 patients with grade 3 or 4 haemorrhoids requiring surgery were recruited and submitted to Ligasure Haemorrhoidectomy. They were compared with 25 patients operated with Milligan Morgan technique with diathermy. All patients were operated by the same two surgeons, who collaborate each other. RESULTS: There were no statistical differences in age, gender or clinical symptoms between the two groups. The mean operating time was 21.1 minutes (range, 15-32 min) in the Study Group and 19.8 min (range, 15-28 min) in the Control Group. Patients were dismissed the same day or the following day after surgery, without statistical differences. Early complications were similar, mainly represented by urinary retention, while late complications were comparable (1 bleeding in each group and 2 late healing in the Control Group). A partial reduction in postoperative pain and a faster healing of postoperative scars were observed in the Study Group. CONCLUSIONS: Ligasure Haemorrhoidectomy is a safe procedure in the treatment of 3rd and 4th grade haemorrhoids. In our study we observed a reduction of postoperative oedema and a faster healing of surgical scars, without affecting postoperative complications.