The effects of fenofibrate on plasminogen activator inhibitor-1 (PAI-1) expression in human umbilical endothelial cell-derived transformed cell line-ECV 304 cells were investigated. ECV 304 cells were incubated with different concentrations of fenofibrate (0, 10, 50, 100 μmol/L) for 24 h. PAI-1 mRNA and protein was detected by reverse transcription-polymerase chain reaction (RT-PCR) and Westblot respectively. PAI-1 antigenic content of endothelial cells was measured by using ELISA. Fenofibrate could inhibit the PAI-1 mRNA and protein expression and reduce PAI-1 antigenic content dependently. After treatment with fenofibrate (10 μmol/L), the expression levels of PAI-1 mRNA and protein were 0.65±0.05 and 0.96±0.11 respectively, significantly lower than in the control group (0.78±0.03 and 1.21±0.15, respectively, P＜0.05). PAI-1 antigenie contents (24.52±8.39) in ECV304 cells treated with 10 μmol/L fenofibrate were significantly lower than those in the control group (6.98±5.12, P＜0.05). It was concluded that fenofibrate inhibited the expression of PAI-1 mRNA in ECV304 cells, and reduce the protein expression and the antigenic content of PAI-1, suggesting that fenofibrate may have an antiatherosclerotic effect on endothelial cells by PAI-1 pathway.