Introduction: Anal fissure is a common benign condition that can cause severe anal pain after defecation and bleeding. Symptoms from fissure cause considerable morbidity and reduction in quality of life. The aim of treatment is to reduce anal hvpertonia, which may improve anodermal blood flow and heal the fissure. Aim of the work: This study aimed to evaluate the effectiveness of local glyceryl trinitrate (GTN) versus surgical lateral internal sphincterotomy in the management of acute and chronic anal fissure. Patients and methods: In our present study we compared topical application of GTN on lipsomal base with the surgical procedure i.e. internal lateral sphincterotomy and according to the method of treatment the patients were divided into two groups; group 1 which included 40 patients with anal fissure and agreed to have the medical treatment with topical GTN 0.2% applied to the anoderm twice daily. Group 2 also included 40 patients and treated with lateral internal