Abstract: AIM: To investigate the effects of endothelial progenitor cell (EPC) mobilization with granulocyte-colony stimulating factor (G-CSF) on neovascularization and to evaluate cardiac function. METHODS: Thirty six adult male rats were divided randomly into control group (saline), myocardial infarction group (MI) and G-CSF treated group ［G-CSF 30 g/(kg·d)］ with saline or G-CSF IP injected for 5 days. The number of EPCs was determined and serum concentrations of VEGF and CRP were measured on the seventh day. Cardiac function was evaluated in vivo and in vitro after 4 weeks. RESULTS: G-CSF mobilization increased the number of circulating EPCs. Compared to the control group, cardiac function in MI group was deteriorated, whereas that in the G-CSF treated group was significantly improved. Mobilization with G-CSF increased the serum level of VEGF and decreased CRP concentration. CONCLUSION: In rats with myocardial infarction, G-CSF promotes the mobilization of EPCs, augments the release of VEGF and improves cardiac function. EPC mobilization with G-CSF is a promising novel therapy for MI.