This prospective study was done to analyze the efficacy of commercial fibrin glue application in the healing of patients with fistulas-in-ano. This clinical trial of 36 patients was performed during the period from November 2003 to May 2004. Thirty men and six women were treated for a fistula-in-ano with commercial fibrin glue application. None of the patients had undergone prior attempts to correct fistulas-in-ano surgically. All patients received preoperative mechanical bowel preparation and prophylactic intravenous antibiotics. In the operating room, the patients underwent an anorectal examination under spinal anesthesia. The external and internal fistula tract openings were then identified. The fistula tract was curetted. Fibrin glue was injected into the external fistula opening until fibrin glue could be seen coming from the internal opening. No dressing was applied over the external opening. Thereafter, the patient was discharged. A 1-week course of oral antibiotics was prescribed. The patients were followed up for 70 weeks with a mean of 54 weeks (range 40-70 weeks). The cause of the fistula-in-ano was cryptoglandular in all patients. The overall initial success rate was 77.8% (28/36). No complications were encountered related to the application. Two patients underwent a reapplication with fibrin glue and the fistulas of these patients were all closed. The overall success rate was 83.3% (30/36). Fibrin glue application was thus found to be an easy, safe, effective, and useful alternative treatment in the management of fistulas-in-ano. However, our findings need substantiation by increasing the number of patients and prolonging the follow-up duration, as well as carrying out comparative studies.