Acute appendicitis (AA) requires a prompt diagnosis. According to postoperative pathological results, a significant number of appendectomies are performed on a normal appendix (NA). The aim of this study is to evaluate the role of preoperative inflammatory markers in supporting and improving the clinical diagnosis of AA, extracting more information from CBC parameters. The study is a retrospective one. The histopathological results of operated appendix from 102 patients, who underwent appendectomy for clinically suspected AA, were extracted from the Galilee Medical Center systems. Two patient groups (NA and true AA) were compared for neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), monocyte to lymphocyte ratio (MLR) and mean platelet volume (MPV). The obtained data were statistically analyzed, using the independent sample t test and Mann-Whitney test. Category data have been compared among groups with the chi-squared test. The primary endpoint of our research was to assess the predictive power of blood biomarkers. Patients with suspected AA, based on clinical picture and contrast enhanced computed tomography (CECT), and with MLR-value ≥0.3357 were 5.25 times more likely than normal to have AA. Patients with NLR-value ≥3.2223 were 7 times more likely than normal to have AA. The differences in PLR and MPV values were not statistically significant. The NLR and MLR biomarkers can assist in diagnosis of AA. This can be particularly helpful in cases where CECT is contraindicated, as in pregnant women or children.