Background: Acute myocardial infarction (AMI) is one of the main etiologies of death globally. In AMI, platelets were demonstrated to play a main role in thrombotic processes that limit the patency of the recanalized, infarct-related coronary artery and contribute to reperfusion injury. Platelet volume is an important indicator for platelet function and activation. Objective: The aim of the present study was to evaluate mean platelet volume (MPV) as an early and independent predictor for AMI in patients with acute chest pain. Patients and methods: This retrospective observational analytical study included a total of 107 patients presenting with acute chest pain presenting to Mansoura Emergency Hospital within the period from January 2019 to January 2020. Of them, 36 cases were diagnosed as stable coronary artery disease and 71 cases were diagnosed as AMI. Results: There were statistically significant differences among both groups regarding age, female sex and BMI being increased in AMI group. Hypertension, DM and dyslipidemia were significantly increased among AMI cases compared to stable coronary artery disease ones. Stable coronary artery disease cases demonstrated significant increase in platelet count and significant decrease in MPV compared to AMI ones. Hypertension, DM, dyslipidemia, family history of CAD, prior MI, prior PCI and MPV could be used as significant predictors for AMI. Conclusion: The current study concluded that larger platelet volumes may be used as predictor for AMI as well as ischemic complications.