Abstract: Objective To analyze the effects of acute normovolemic hemodilution(ANH) on hemodynamics, blood components and allogeneic blood volume during off-pump coronary artery bypass grafting. Methods Sixty-eight patients undergoing off-pump coronary artery bypass grafting in our hospital from January 2015 to August 2017 were randomly assigned into the research group(n=34) and the control group(n=34). Patients in the research group received ANH after induction of anesthesia, while the control group did not. The postoperative coagulation function, blood component changes at different time points, hemoglobin(Hb), central venous pressure(CVP), HR and MAP immediately after induction of anesthesia, and at 10 min, 30 min, 1 h, 2 h after ANH and1 h after completion of autologous blood transfusion, perioperative crystal, colloid and allogeneic blood dosage, were compared between the two groups. Results Two-factor repeated measurement variance analysis showed that there were significant effects of time on neutrophils, lymphocytes, red blood cells and white blood cells(all P<0.05), but no difference was found in interaction and between groups; Hb, CVP were significantly lower in research group than control group after surgery(all P<0.05). During operation, the dosage of colloid in the research group was significantly higher than that in the control group(P<0.05); At 24 hours after surgery, the volume of urine, dosage of plasma and erythrocyte concentrate in the research group were significantly lower than those in the control group, and the dosage of colloid was significantly higher than that in the control group(all P<0.05). One day after operation, the prothrombin time, activated partial thromboplastin time and thrombin time of the two groups were significantly higher than those before operation(all P<0.05), but the difference between the two groups was not statistically significant; the fibrinogen of the research group was significantly lower than that of the control group(P<0.05). Conclusion The application of ANH in off-pumped coronary artery bypass grafting is beneficial to reduce the amount of allogeneic blood, and its effects on patients' blood coagulation function and hemodynamics was not inferior to traditional blood transfusion.