Objective This article mainly discusses the clinical effect of transcter approach combined with loose seton in the treatment of complex anal fistula. Methods Selecting 80 patients with complex anal fistula admitted to our hospital from May，2020 to July 2022，Randomly divided into treatment group and control group.40 cases in the treatment group（N = 40）and 40 cases in the control group（N = 40）. The patients in the treatment group used intersphincter approach combined with relaxtion thread drawing. The patients in the control group were circumcised by cutting and drainage to compare the operation time，hospitalization time and wound heal⁃ ing time between the two groups. VAS，functional recovery（anal canal rectal pressure measurement and Wexner in⁃ continence score）. Results Clinical curative effect was achieved in both groups. There were no significant differ⁃ ences in cure rate，preoperative anal function（anorectal pressure measurement，Wexner incontinence score）and VAS score on the 7th day after surgery between the two groups（P > 0.05）. There were significant differences in length of hospital stay，wound healing，operation time and VAS scores 1，3 and 5 days after surgery（P < 0.05）. There were significant differences in anorectal pressure measurement（anal resting pressure and anal retraction pressure）and Wexner incontinence score more than 3 months after surgery between the two groups（P < 0.05）. Conclusion The treatment of complex anal fistula through intersphincter approach combined with loose seton has obvious advantages in functional protection（anorectal pressure measurement，Wexner score），wound healing and postoperative pain compared with traditional cutting and drainage. It has been proved that the treatment of compli⁃ cated anal fistulas by intersphincter approach combined with relaxation and hanging line is safe and effective for the protection of anal function and worthy of popularization and application. 

"> transsphincter intermuscular approach, loose seton, complex anal fistula, clinical ef? fect