In this study, we investigated the sliding friction of human umbilical vein endothelial cell (HUVEC) monolayer cultured on poly(sodium p-styrene sulfonate) (PNaSS) gel, intending to elucidate the role of the glycocalyx on the surface of endothelial cell (EC) in friction reduction. Three sets of HUVEC monolayers were investigated: 1) as-cultured HUVEC monolayer, 2) HUVEC monolayer treated by transforming growth factor υ1 (TGF-υ1), which increased glycocalyx by 148%, 3) HUVEC monolayer treated by heparinase I, which reduced glycocalyx by 57%, both were compared with that of the as prepared one. When being slid on flat glass surface, the frictional stress of HUVEC monolayer decreased in the order of heparinase I-treated > as-cultured > TGF-υ1-treated samples. The results suggested that glycocalyx may play a role in reducing the friction of endothelial cell monolayer.