Abstract: Objective To compare the effect and safety of thromboelastography and standard coagulation tests guided perioperative period transfusion in patients undergoing cardiac surgery with cardiopulmonary bypass. Methods Ninety-six patients undergoing cardiac surgery with cardiopulmonary bypass were randomly divided into group TEG (group T, n=48 ) and group SCT (group C, n=48). The perioperative period transfusion in Group T was guided by TEG, and in Group C by SCT. The volume of haemorrhage and the consumption of different blood components during perioperative period were recorded; the incidence of reoperation or die, and the intubation time and length of ICU stay and hospitalization time of both groups were also observed. Results There were no difference in the volume of haemorrhage, the consumption of fluid crystalloid and colloid, the consumption of autologous blood and allogeneic RBC between the two groups (all P>0.05). The consumption of allogeneic FFP and PLT were significant decreased in Group T as compared wht Group C(all P<0.05). There were no difference in the incidence of reoperation or die and the intubation time and length of ICU stay and hospitalization time between the two groups (all P>0.05). Conclusion Compared with SCT, TEG guided transfusion algorithm may reduce the consumption of allogeneic FFP and PLT, while not elevate the volume of haemorrhage and RBC input and not decrease the clinical efficacy.