Abstract: The hypertensive disorder happened in pregnancy after 20 weeks，in China the average morbidity was 9.4%；it could be the second reasons which leads to death of the pregnant women. The pathogenesis had not yet completely clear，it might relate to vascular endothelial injury，activation of coagulation，fibrinolysis system and platelet dysfunction. Platelets were the smallest and non-nuclear components in the blood，when activated the platelet secretion， adhesion and aggregation then made up the platelet thrombus. In the recent years，lots of studies had shown that the activation，adhesion，aggregation and other functional changes of platelet played an important role in the progress of the disease. This article summarizes the research progress in platelet activation and hypertensive in pregnancy.

Key words: Hypertension, pregnancy-induced, Platelet count, Platelet activation, Platelet aggregation, Platelet adhesiveness