<p>Non-cure, recurrence and faecal incontinence have often been a major challenge in patients after surgical treatment for anal fistula. To overcome these problems, we have developed a sphincter-preserving total fistulectomy procedure involving resection of the anoderm and skin with intersphincteric space closure (TFRAS). The purpose of the present study was to evaluate this TFRAS technique. TFRAS was performed in 618 patients. The method involved excision of the anoderm and skin, including the internal opening, total removal of the fistula tract while preserving the sphincter, closure of the resulting intersphincteric space and open wound. The Parks classification was used, and subcutaneous, supralevatoric, and unclassifiable fistulas not included in this classification were newly defined and evaluated. The postoperative cure rate was 97.7% and the recurrence rate was 0.7%. The non-cure rate was significantly higher for supralevatoric fistulas and the recurrence rate was significantly higher for unclassifiable fistulas. No cases of postoperative solid faecal incontinence were observed, and the faecal incontinence rate was 0.7%. The mean postoperative Cleveland Clinic Faecal Incontinence (CCFI) score was 0.9, and the highest value of 8 was observed in only one case. No significant differences were found between the classifications based on faecal incontinence rates and the CCFI score. There was no significant difference in CCFI score between patients who underwent TFRAS at only one site and those who did so at two or more sites. TFRAS is considered a useful technique for anal fistulas, offering a high cure rate, a low recurrence rate, and no severe postoperative faecal incontinence.</p>