Abstract: 【Abstract】 Objective To analyze the risk factors and prevention measures for postpartum hemorrhage. Methods 3786 cases who gave birth in our hospital from May 2011 to December 2011 were analyzed retrospectively. The Logistic regression was used to analysis the risk factors of the postpartum hemorrhage. Results Based on the amount of blood loss, measuring by the weight and volume estimation, there were 135 cases out of 3786 defined as postpartum hemorrhage and the incidence was 3.57%. Due to the single factor analysis, there were 11 factors associated with postpartum hemorrhage, including age, delivery history, the manner of delivery, placenta previa, placental abruption, adherence implantation or residual of placenta, uterine atony, injury of birth canal, anemia, coagulation disorders, pregnancy-induced hypertension history. According to the multiple factor analysis, 4 factors entered the logistic regression model, including uterine atony (OR=15.132，95%CI 13.342~16.701）, placenta previa (OR=10.897，95%CI 9.256~11.347 ）, adherence implantation or residual of placenta (OR=30.310，95%CI 23.312~35.514）and cesarean section (OR=4.018，95%CI 3.331~4.522 ）. Conclusion Uterine atony, placenta previa, adherence implantation or residual of placenta and cesarean section were the risk factors of the postpartum hemorrhage. Pay attention to prevent the uterine atony. Strengthen the knowledge of perinatal care as much as possible and reduce the rate of cesarean section can help reducing the incidence of postpartum hemorrhage and obstetric mortality.