Background: Appendicitis is one of the most common surgical emergency in general surgical practices. Early and prompt diagnosis is necessary to avoid life-threatening complications associated with it. Hence this study was conducted to evaluate the hyperbilirunemia as predictive marker in acute appendicitis and appendiceal perforation. Methods: Al cases of acute appendicitis and appendicecal perforation fulfilling inclusion and exclusion criteria taken up for this prospective observational single center study which were confirmed histopathologically in per operative setting. Results: Total 100 patients were in the study of which 33 patients had appendicecal perforation of which 23 patients had hyperbilirubinemia (70%) . 67 patients had acute appendicitis of which 42 patients had hyperbilirubinemia , 37%. Hyperbilirubinemia with a cutoff point of 0.9 mg% for appendicitis patients has a sensitivity of 85.3%, a specificity of 77.2%, a positive predictive value of 36%, and a negative predictive value of 91%. Hyperbilirubinemia with a cutoff point of >1.3 mg% for appendiceal perforations has a sensitivity of 75%, a specificity of 81.2%, a positive predictive value of 83%, and a negative predictive value of 88%. Conclusion:Hyperbilinemia is seen in acute appendicitis predominantly in appendiceal perforation hence evaluation of serum bilirubin level preoperatively can predict possibility of appendiceal perforation as it is easily available , cheap and simple laboratory test.