Platelet indices have been linked to the severity and prognosis of coronary artery disease, but a very small number of studies assessed them under dual antiplatelet therapy after percutaneous coronary intervention (PCI). The aim of this study was to evaluate changes in mean platelet volume (MPV), platelet distribution width (PDW) and platelet-large cell ratio (P-LCR) in these patients. A number of 437 patients with stable coronary artery disease, 131 patients with non ST segment elevation acute coronary syndrome and 151 patients with ST segment elevation myocardial infarction were included in the study. There was no difference between the three groups regarding platelet indices prior to PCI. Follow-up data was available for 181 patients, at a mean follow-up time of 69 (46-98) days. MPV, PDW and PLC-R were similar to those prior to PCI in all three groups. Regarding the P2Y12 inhibitor, clopidogrel or ticagrelor, there was no difference at follow-up between platelet indices irrespective of the indication for PCI.