INTRODUCTION: Although lateral internal sphincterotomy (LIS) is the most preferred surgical treatment for chronic anal fissure, In this study, we aimed to investigate the effect of preoperative anorectal manometry on surgical treatment choice in patients presenting with anal fissure. MATERIAL AND METHODS: Between January-2015 and August-2017 and whose physical examination revealed chronic anal fissure findings were included in the study. Patients were divided into two groups as Group 1 LIS and Group 2 non-LIS. In addition to the demographic characteristics of the patients, anal manometry findings and its effect on surgical treatment options were examined. RESULTS: 20 patients (M/F:13/7) were included in the study. The mean age was 48.3+17.4 in Group 1 and 45.25 +24.45 in Group 2 (p:0.797). In the preoperative manometric examination, resting pressure(mmHg) range was 93.2+15.9 in Group 1, and44+11.2 in Group 2 (30-57) (p:0.001). Endurance to squeezing time was shorter in Group 2 (p:0.0138). There were no differences between the groups in terms of mean squeezing pressure, rectal sensation, and rectoanal inhibitor reflex (p>0.05). Of the four patients with low sphincter pressures, 3 underwent botulinum toxin injection and 1 underwent advancement flap instead of LIS. There was no significant difference between preoperative and postoperative CCFI scores in the LIS group (0.6±1.8 vs. 1.2±1.85, p>0.05). CONCLUSION: In the treatment of chronic anal fissure, non-LIS methods were selected in 20% of the patients with the help of preoperative anal manometric examination. Manometric examination is important to minimize the risk of incontinence and to determine the choice of treatment correctly.