Objective：To investigate physiological changes of coagulation factors activity and their influencing factor during normal pregnancy. Methods: Healthy pregnant women and non-pregnant women who were examined (n=80) in hospital from September to November in 2012. Early pregnancy group (G5-8W，n=20), Middle pregnancy group (G25-28W，n=20), Late pregnancy group (G35-38W，n=20), a control group of nonpregnant women (n=20).Used CA-1500 Automatic blood coagulation analyzer and related reagents, we had established the standard curves of levels each of coagulation factors included FⅡ:C, FⅤ:C, FⅦ:C, FⅧ:C, FⅨ:C, FⅩ:C, FⅪ:C, FⅫ:C which we had collected. Results: A total of 80 patients were included in the study, in early pregnancy, FⅦ:C, FⅨ:C were decreased (P＜0.05), FⅡ:C, FⅦ:C, FⅩ:C, FⅫ:C were significantly lower than mid- pregnancy（P＜0.05）.Compared with the mid-pregnancy, FⅡ:C had an upward trend in late-pregnancy （P＜0.05），remaining factors were also significantly higher in it（P＜0.01）.Compared with the early pregnancy, FⅡ:C were significantly higher in late- pregnancy （P＜0.01）, FⅧ:C had an upward trend in late-pregnancy（P＜0.05）. Conclusions: FⅦ:C, FⅨ:C decreased during early pregnancy，which maybe play a role in the established of maternal uterine-placental blood circulation. FⅡ:C, FⅤ:C, FⅦ:C, FⅧ:C, FⅩ:C, FⅫ:C elevated in the middle and late pregnancy, which promoted that the blood of pregnant women during pregnancy is a hypercoagulable state. Key words: gestation; blood coagulation factor; activation