Background : Acute appendicitis is one of the emergency cases that can cause death if not diagnosed and handled quickly and appropriately. Because perforation can occur appendix and the occurrence of life-threatening peritonitis. Diagnosis is an important step so that acute appendicitis can be treated immediately. Alvarado scoring system and modified Alvarado score is a simple scoring system for diagnose acute appendicitis easily and quickly. The purpose of this study is to know the comparison the use of Alvarado score with modified Alvarado score to establish acute appendicitis. Methods : This study is a diagnostic test study with cross sectional design to determine the diagnostic value of Alvarado score and modified Alvarado score. This study uses retrospective data taken from medical records and patient histopathology results at Brebes General Hospital in September 2016 until May 2017. Chi Square Test is used to process data that is nominal or ordinal whereas Wilcoxon Test is used to compare the diagnostic value of each scoring system. Results : The results of Alvarado score, modified Alvarado Kalan score, and modified Alvarado Phophrom score for sensitivity value of 81.5% v.s. 76.6% v.s. 85.1%, specificity of 67.4% v.s. 86.0% v. 81.4%, positive predictive value of 74.1% v.s. 85.7% v.s. 83.3%, negative predictive value of 80.6% v.s. 77.1% v.s. 83.3%, and accuracy of 76.7% v.s. 81.1% v.s. 83.3%. The results of statistical measurements showed no significant difference between the use of Alvarado score with Alvarado score modification, except the specificity score of Alvarado score with Alvarado Kalan score modification which had significant difference (p = 0,028). Conclusions : Modified Alvarado score can be used to replace Alvarado score for diagnosing acute appendicitis.