ObjectiveTo evaluate clinical curative effect of sphincter preservation method of improved minimally invasive surgery to primary cure for horseshoe-shaped perianal abscess. MethodsOne hundred and twenty hospitalized patients diagnosed as horseshoe-shaped perianal abscess were analyzed by prospective, random, single-blind, parallel-group design method, and were randomly divided into two groups, one group of sphincter preservation method of improved minimally invasive surgery (observation group), another group of traditional method of hanging line drainage and multiple incisions of radian shape (control group). The cure rate, long-term recurrence, postoperative pain score within 9 d, hospitalization time, incision healing time, scar area after healing, postoperative anal function score and perioperative and long-term complications were compared in these two groups. ResultsAll the operations were successfully completed in these two groups. There were 56 cases of primary healing in the observation group and 55 cases of primary healing in the control group. Compared with the control group, the postoperative pain score on day 2-4 or on day 7-9 was lower (P < 0.05), the incision healing time was shorter (P < 0.05), and the postoperative anal function score was lower (P < 0.05) in the observation group. There was no incision infection and hemorrhoea in these two groups. The hospitalization time, scar area after healing, incidence rate of urinary retention, hepatic and renal dysfunction, and the total white blood cells > 10.0×109/L had no significant differences between these two groups (P > 0.05). There was no long-term recurrence, anal stenosis, and anal incontinence during following-up of 6 months in these two groups. ConclusionPreliminary research results show that sphincter preservation method of improved minimally invasive surgery to primary cure for horseshoe-shaped perianal abscess has a reliable clinical curative effect, fast healing, and less postoperative complications.