Background: Anal fissure is defined as an ulcer in the anoderm usually in the posterior midline, less frequently in the anterior midline and rarely in the lateral position of the anal canal. Different treatment modalities include non-invasive pharmacological therapies, lateral internal sphincterotomy (LIS) which is the gold standard for treatment and new therapies that include perineal support devices, Gonyautoxin injection, fissurectomy, fissurotomy, sphincterolysis, and flap procedures. Thus, aim of the study was to compare the efficacy of outcome of lateral internal sphincterotomy and subcutaneous fissurectomy with topical 2% Diltiazem gel in the treatment of chronic fissure in ano.Methods: 50 patients with chronic fissure in ano attending OPD of Department of General Surgery, KVGMCH, Sullia were randomly selected and divided into Group A (n=25): Lateral internal sphincterotomy (control group) and Group B (n=25): Subcutaneous fissurectomy + topical 2% Diltiazem Gel (test group).Results: Patients of Group B showed much less mean duration of absenteeism (2.88 weeks) compared to Group A. Comparison between Group B and Group A showed statistically significant differences in pain relief (P<0.0001), complications (p=0.03), mean duration of sitz baths (p<0.0001), absenteeism (p<0.0001) respectively.Conclusion: Hence Subcutaneous fissurectomy with topical 2% Diltiazem gel is a better surgical option for chronic fissure in ano than conventional Lateral internal sphincterotomy.