Purpose: This prospective study was done to analyze the efficacy of commercial fibrin glue application in the healing of patients with fistulas-in-ano from a long-term (mean 4.5 years) research period. Methods: This clinical trial of forty-six patients was performed during the period from January 2004 to February 2005. Thirty-nine men and seven women were treated for a fistula-in-ano with a commercial fibrin glue application. 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 the fibrin glue could be seen coming from the internal opening. Results: The overall initial success rate was 86.95% (40/46). Recurrence rate was 41.30% (19/46). Two patients underwent a re-application with fibrin glue and the fistulas of these patients closed. The total recurrence rate was 36.95% (17/46). The long-term overall success rate was 63.04% (29/46). Conclusion: Fibrin glue application was thus found to be an easy, safe, acceptable, successful alternative treatment in the management of fistulas-in-ano. Choosing the patient correctly is very important because long (more than 4 cm) and non-ramificate fistula tracts usually close with commercial fibrin glue.