Objective To explore the value of ultrasound-guided balloon control technique in abdominal aorta for reducing intraoperative hemorrhage in high-risk placenta previa undergoing cesarean section.Methods From Aug 2013 to Oct 2017,40 cases were admitted,among them,16 cases were treated with ultrasound-guided towed balloon prophylactic control technique of abdominal aorta (the study group) before cesarean,and 24 cases did not receive balloon occlusion (the control group) during the cesarean.Clinical data were compared between the two groups.Results The time used for uterine suture (t =10.34,P =0.01),the amount of intraoperative blood loss (t =9.51,P =0.01) and blood transfusion (t =3.41,P=0.005)in the two groups were all statistically different.While the differences in PT (t =1.02,P =0.32),ALT (t =0.54,P =0.59),AST(t =0.91,P =0.37),creatinine(t =0.75,P =0.46) were not statistically significant between the two groups.Conclusion Ultrasound-guided abdominal aortic balloon control technique can reduce the blood loss significantly in cesarean section with high-risk placenta previa.