Abstract：Objective To investigate the characteristics and pregnancy outcomes of late pregnancy pernicious placenta previa , and improve the understanding．Methods 40 patients with pernicious placenta previa admitted to our hospital were selected as group A, and 60 patients with ordinary placenta previa were chosen as the group B．The clinical data were analyzed by using the statistical methods. Results Compared the placenta previa types of the patients in two groups， the difference was no statistical significance（P>0.05）; The placental implantation, postpartum hemorrhage, in traoperative blood loss, hysterectomy and blood transfusion of patients in group A were higher than that of group B(P<0．05), compared the neonatal outcomes in two groups, the difference was no statistical significance（P>0.05）。Conclusion The main risk factors of dangerous placenta previa for lying-in woman and neonatus are postpartum hemorrhage and placenta implantation of the patients with pernicious placenta previa, in traoperative blood loss and hysterectomy, good prevention and emergency measures can reduce the danger of lying-in woman and neonates.