Hemorrhagic fever with renal syndrome (HFRS) is an acute infectious disease characterized by endothelial cell dysfunction, which results in plasma exosmosis, hyperpermeability, and sometimes hemorrhages. As one of the vascular permeability cytokines, vascular endothelial growth factor (VEGF) might mediate the hyperpermeability caused by HFRS. In the present study, the levels of serum VEGF were measured by competitive inhibition ELISA. We found variable but persistently elevated levels of VEGF throughout the various stages and types of HFRS disease, which suggested that the levels of VEGF were closely correlated to the progression of HFRS. Moreover, elevated levels of VEGF have correlation with the severity and degree of kidney damage. Therefore, to study the relationship between levels of VEGF and disease severity of patients with HFRS is helpful to clarify the pathogenesis of HFRS.