Early and complete restoration of blood flow in closed coronary arteries is the main goal in treating patients with myocardial infarction. Primary angioplasty is not always successful in establishing myocardial blood flow. Although the strategy of adding eptifibatide leads to better blood flow, its value as part of a routine strategy is questionable. Therefore, this study was performed to evaluate the efficacy of intravenous eptifibatide in primary percutaneous coronary intervention (PCI) patients. This clinical, randomized, double-blind trial was performed on patients aged 20-80 years undergoing primary PCI. The patients were selected for study by convenience sampling and were randomly divided into two equal groups. The first group was treated with intravenous eptifibatide immediately before angioplasty with heparin. The second group received only coronary angioplasty with heparin. After data collection, statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS) software, version 16. A total of 104 patients were enrolled in the study, and there were no statistically significant differences in terms of age (P=0.188), gender (P=0.345), risk factor (P>0.05), or history of PCI (P=0.199). Mean thrombolysis in myocardial infarction (TIMI) score was not significant between the two groups after receiving the drug and performing angioplasty (P>0.05), and the rate of ejection fraction was 46.33±6.69 in patients receiving eptifibatide and 47.54±4.67 in the heparin group, which was not statistically significant (P=0.884). We found that eptifibatide improves clinical indexes in patients undergoing primary PCI, but these differences were not significant in the two groups.