Objective:The pathogenesis of placental vascular disease(PVD) was further investigated. Methode:PVD group (study group) and normal pregnancy (control group) were recruited. Two-channel mi-croarray technique was applied to screen the most differently expressive genes of human genome, and veri-fied the different expressions in mRNA and protein levels by quantitative PCR and Westem-blot, also local-ized the expression of different genes in placental tissue by immunohistochemistry. Reeults:HspA6 and Hs-pA1A had extremely higher expression in placentas with PVD than normal pregnancy. These genes both en-coded Hsp70. Hsp70 was mostly expressed in endothelial and smooth muscle cells of placental microves-ssls. The expression of Hsp70 mRNA and protein were up-regulated in placental tissue and microvascular endothelial cells from PVD group compared with normal pregnancy ( P <0.05) ;The expression of Hsp70 mR-NA and protein had negative correlation with infant birth weight ( P < 0.05). Conclueione:Hsp70 was associ-ated with endothelial activation in the pathogenesis of PVD by initiating an innate immune response and in-flammatory reaction.