Postdilation is frequently used during coronary interventions to prevent stent malapposition. Currently there are contradictory findings regarding the benefits of postdilation for both intraprocedural and long-term outcomes. We evaluated the impact of postdilation among patients who presented with acute coronary syndromes (ACS) and underwent percutaneous coronary interventions (PCI). A total of 258 consecutive patients who presented with ACS and underwent PCI were included in the study. The patients were followed up for 25 +/- 1.7 months for the occurrence of major adverse cardiovascular events (MACE). During follow-up, 65 patients (25.2%) had MACE. Among patients without MACE, intracoronary nitrate infusion was less frequently used (P= 0.005), myocardial blush grade was higher (P < 0.001), and a drug-eluting stent was more frequently used (P= 0.005). No significant differences were noted between groups regarding the predilation, recurrent dilation, postdilation, and other angiographic characteristics. In multivariate analysis, female sex (P= 0.047), myocardial blush grade (P = 0.038), previous coronary artery disease (P = 0.030), and peak troponin level (P = 0.002) were found to be predictors of MACE. In patients who were treated with PCI for ACS, performing postdilation did not predict final Thrombolysis in Myocardial Infarction (TIMI) flow grade, corrected TIMI frame count, myocardial blush grade, or MACE.