Aim: To study the diagnostic role of rise in bilirubin in Acute appendicitis. Materials and method: Prospective analytical study of Pre-operative Role of Rise in Bilirubin in acute appendicitis was carried out in December 2019 – April 2021. All cases coming with uncomplicated acute appendicitis admitted during study period in Sharda Hospital, Gr. Noida, UP. were included in study. Patients with Pre-operative diagnosed case of acute appendicitis with age above 18 years were included. The patients with Complicated appendicitis, Negative proved specimen on Histopathalogy Examination, Patients suffering from Positive HBs Ag, Previous history of Jaundice, Chronic Alcoholism (daily intake of >40 ml for male &>20 ml for female),Patients suffering from Hemolytic Disease, Congenital biliary disease, Hepato-biliary malignancy, Recent history of liver trauma, Cholelithiasis, Females with history of oral contraceptive pill, Patients with history of Statins, Pregnancy were excluded from the study. A detailed history, complete physical examination and routine & appropriate investigations were done for all patients.