Background: The certainty of diagnosing acute appendicitis in patients presenting with right iliac fossa pain still remains a mystery though acute appendicitis being the commonest surgical procedure done in emergency. In acute appendicitis, serum bilirubin levels are raised due to hepatocellular damage as a result of direct insult caused by Gram-negative bacterial endotoxemia. The need for the study is to conclude whether the serum bilirubin can be considered as a new laboratory marker to aid in the diagnosis of acute appendicitis and if so, does it have the predictive capacity to warn us about appendicular perforation. Materials and methods: This is a prospective study carried out at rural tertiary healthcare center and includes 213 patients clinically diagnosed as acute appendicitis. Results: Out of 213 patients, raised serum bilirubin ≥1.2 mg/dl was present in 195 (91.5%) patients, out of which 194 (99.4%) patients had histopathologically inflamed appendix and this difference was statistically highly significant with p-value < 0.0001. In this study, 32 patients had perforated appendix. Out of those, 30 patients had bilirubin ≥ 4 mg/dl and 2 patients had bilirubin level between 1.2 and < 4 mg/dl. Raised serum bilirubin (≥4 mg/dl) was present in 35 (17.9%) patients, out of which 30 (87.7%) patients had perforated appendix.