Chronic anal fissure is one of the most common benign anorectal health conditions, causing significant morbidity, quality of life, and economic loss. Eight randomized controlled trials with a total population size of 1035 were eligible for analysis. Seven studies included both males and female, while one only included females. The majority of randomized controlled trials involved female dominance [54.9% (43.5–66.3)] and posterior midline location [86.1% (95% CI 81.5–90.8%)]. This meta-analysis of randomised control trials found that overall postoperative healing was 90.2%, recurrent anal fissure was 3.7%, and postoperative incontinence was 8.9% after LIS. Even though there was no statistically significant difference, closed lateral internal sphincterotomy (LIS) had higher rates of recurrent anal fissure (RR = 1.73 (95% CI 0.86–3.47, p = 0.90, I2 = 0%) and lower rates of postoperative incontinence rate (RR = 0.60 (95% CI 0.37–0.96, p = 0.76, I2-0) as compared with open LIS. We recommended that closed lateral internal sphincterotomy (LIS) is a safe and effective surgical treatment option for chronic anal fissures.