Objective To investigate how fluid shear stress regulates the expression of tissue factor (TF) in Endothelial cells. Methods The endothelial cells were subjected to fluid shear stress of 12 dyn/cm2(1 dyn/cm2=0.1 Pa) for 20 min in the flow chamber, and then the expression of Egr-1 and Sp1 during the expression of TF gene were detected by elector-phoretic mobility shift analysis (EMSA) and Western Blot (WB). Results (1) Only the expression of Spl was detected in static group and no Egr-1 expression was found; (2) Shear stress caused the level of phosphorylated Sp1 and the expression of Egr-1 increasing; (3) EMSA showed that Egr-1 had more competence than Sp1 in binding sites of the Sp1/Egr-1. Conclusion The nuclear transcription factors could play different roles in the process of the expression of TF gene: Spl is crucial to the basal expression of TF gene in the static condition, the displacement of Sp1 by Egr-1 and phosphorylated Sp1 may be involved in the expression of TF gene induced by fluid shear stress.