Aim To investigate the relationship between vascular dysfunction and change of functional activities of circulating endothelial progenitor cells (EPC) in hypertensive urgency. Methods Thirteen hypertensive urgency patients(n＝13) and twenty normotension(n＝20) were recruited for the research. First of all, blood samples were collected and circulating EPC were isolated and cultured. The migration, proliferation and adhesion activities of circulating EPC were detected with Transwell method and CCK-8 assay respectively.In addition, the level of granulocyte-macrophage colony stimulating factor (GM-CSF), vascular endothelial growth factor (VEGF) and interleukin-6(IL-6) from both plasma and EPC production were measured by ELISA. The level of nitric oxide (NO) from both plasma and EPC production were determined by nitrate reductase method. Finally, brachial artery-based flow mediated dilatation (FMD) was used to determine vascular endothelial function. Results Compared with the normotension group, the migration, proliferation and adhesion activities of circulating EPC, the level of NO from both plasma and EPC production were dramatically decreased in hypertensive urgency group(P＜0.05). Furthermore, there was a strong correlation between FMD, NO (from both plasma and EPC production) and circulating EPC activities (migration, proliferation and adhesion activities).However, there were no significant differences among the level of GM-CSF, VEGF and IL-6 from both plasma and EPC production in two groups(P＞0.05). Conclusion The functional activities of circulating EPC were declined in hypertensive urgency, which is positively correlated with the level of NO and FMD.