Background: Acute appendicitis is the most common surgical emergency and appendectomy remains the most frequently performed emergency operations world wide. Aim: To minimize negative appendectomy in the General Surgery department in Zagazig University hospitals and to put a protocol to deal with suspected cases in the future. Methods: this study was carried out in the emergency unit of General Surgery department of Zagazig University Hospitals between the period from January 2018 to January 2019, the study included 112 patients suspected to have acute appendicitis. Complete blood count (CBC), C-reactive protein (CRP), Serum bilirubin (S. bilirubin) were estimated for all patients preoperative. Results: From the results we found that from 39 complicated cases TLC was negative in 2 cases only and regarding to CRP it was negative in 4 cases, also we found that S.bilirubin was positive in 38 cases. from these cases 26 were complicated. S.bilirubin was positive in only 1 case of negative appendectomy cases. Conclusion: white cell count, C-reactive protein and Serum bilirubin measurements are useful in the assessment of acute appendicitis. If used judiciously, they may spare a group of patients not only an unnecessary surgical procedure, but also unnecessary admission to hospital for observation