Background: Differentiating Between Acute Coronary Syndrome (ACS) and Stable Coronary Artery Disease (SCAD) necessitates sophisticated laboratory instruments and electrocardiograms. However, such resources are often scarce in primary care settings in developing countries. Given that hematologic changes frequently manifest in ACS patients, they could offer valuable insights for distinguishing ACS from SCAD. Aim: This study examines the hematologic indices in both ACS and SCAD patients, assessing their potential as predictive markers for identifying ACS. Methodology: A total of 121 participants, comprising 51with ACS and 70 with SCAD, met the inclusion criteria for this study. Patient characteristics, hematologic indices upon admission, and the ultimate diagnosis were extracted from medical records. Statistical analyses were conducted using SPSS 23.0. Results: In this study, MCHC value (32.42 vs. 31.78g/dL; p < 0.05), WBC (10.26 vs. 6.32 x 109/L; p < 0.001), NLR (6.35 vs. 3.27; p < 0.001), and PLR (177.65 vs. 126.65; p < 0.001) were found to be significantly higher in ACS patients compared to those with SCAD. Conversely, MPV (6.42 vs. 10.12fL; p < 0.001) was significantly lower in ACS patients. ROC curve analysis revealed that MPV had the highest AUC (95%) for diagnosing ACS, with an optimal cut-off point at ≤ 8.35fL, providing a sensitivity of 93.5% and specificity of 96.8%. Conclusion:Significant differences were observed in hematologic indices between ACS and SCAD patients, with mean platelet volume (MPV) emerging as the most effective indicator for distinguishing ACS.