Background: To investigate the clinical effect of sphincter repair combined with perineal body reconstruction in the treatment of old fourth-degree perineal tears. Method: A prospective database of five patients with old fourth-degree perineal tears treated between January 2015 and January 2021 was established and studied retrospectively. Results: All five patients were followed-up with for 1 year, and anal incontinence was cured. The anal function recovered, and the anal shape was satisfactory. Three months after the operation, transperineal ultrasonography showed continuity of the anal sphincter, anal mucosa, and perianal skin. Anorectal manometry was performed 3 months after the operation. The anal resting pressure (56.20 \pm 3.42 mmHg), the maximum anal systolic pressure (90.00 \pm 5.39 mmHg), and the maximum anal systolic time (20.80 \pm 3.77 s) were significantly higher than the preoperative anal resting pressure (11.80 \pm 1.79 mmHg), maximum anal systolic pressure (31.40 \pm 3.21 mmHg), and maximum anal systolic time (8.40 \pm 1.52 s), respectively (t = –25.720, p 0.01; t = –20.902, p 0.01; t = –6.826, p 0.01). The Wexner scores at 3, 6, and 12 months after the operation were (1.00 \pm 0.71), (0.40 \pm 0.55), and (0.20 \pm 0.45), respectively, which were significantly lower than the preoperative Wexner score (15.00 \pm 1.00) (t = 25.560, p 0.01; t = 28.633, p 0.01; t = 30.210, p 0.01). Conclusions: Transperineal sphincter repair combined with perineal body reconstruction is safe and effective in the treatment of old fourth-degree perineal tears. The initial results are encouraging, indicating the need for a more formal evaluation of the technology.