Objective To observe the dynamic changes of endothelial progenitor cells (EPC)and vascular endothelial growth factor (VEGF) in the patients with acute myocardial infarction (AMI)after percutaneous transluminal coronary intervention (PCI). Methods The level of VEGF before and after PCI in 50 cases with AMI were determined by fluorescence immunoassay and enzyme-linked immunosorbnent assay (ELISA),and the ratio of EPC in flood was checked by flow cytometry.Results The level of EPC was higher after PCI than before PCI [(4.15 ± 0.22)％ vs.(0.59 ±0.02) ％,P＜0.01],and there were positive correlations between EPC and number of coronary artery disease (r=0.45,P ＜ 0.05 ),coronary artery lesions ( r =0.76,P ＜ 0.01 ),left ventricular enddiastolic diameter (r=0.68,P＜0.01),ejection fraction (r=0.75,P＜0.01).The VEGF levels after PCI was increased [(506± 120)μg/L vs.(204±98)μg/L,P＜0.01],and its level was positively related with coronary lesions (r=0.66,P＜0.01),left ventricular ejection fraction(r=0.90,P＜0.01).There was association between rising rates of EPC and VEGF in a short time after PCI within 24 h period (r=0.56,P＜0.01). Conclusions The clinical efficacy and prognosis can be assessed by the changes of VEGF level and EPC ratio before and after PCI operation in AM1 patients.