Abstract: Introduction The case of appendicitis is a surgical emergency that is very often encountered with the most common complications in the form of necrosis and perforation of appendicitis which is an abdominal emergency that requires immediate surgery. Difficulty in diagnosing results in increased morbidity, more complications, longer hospital stays and higher costs. There were 60 cases of acute appendicitis recorded at Haji Adam Malik Hospital Medan in 2009. There is no good scoring system as a predictor of necrotizing appendicitis cases, but based on several studies the use ofalvarado score and LRINEC (Laboratory risk indicator for necrotzing fasciitis) can be used to improve diagnostic procedures and determine the risk of developing necrotizing fasciitis. The researcher wanted to know the accuracy comparison between ALVARADO score and LRINEC score as a predictor of the incidence of necrotizing appendicitis at H. Adam Malik Hospital, Medan.