Objective To explore the clinical effect of evidence-based nursing in preventing postpartum hemorrhage in cesarean section. Methods A total of 280 pregnant women who underwent cesarean section in Liangxiang Hospital,Fangshan District, Beijing from May to October 2021 were selected as research objects, and they were divided into observation group (n=140) and control group (n=140) by random number table method. The control group was given routine nursing measures, and the observation group was given evidence-based nursing intervention on the basis of routine nursing. The bleeding volume during operation, 2 h and 24 h after operation, red blood cell (RBC), hemoglobin (HGB),red blood cell volume (HCT) and complication rate before operation and 24 h after operation were compared between the two groups. Results There was no significant difference in intraoperative blood loss between the two groups (P＞0.05).Blood loss at 2 h after surgery in the observation group was significantly lower than that in the control group, with statistically significant differences (P＜0.05). In the control group, there was no significant difference in blood loss between during surgery and at 2 h after surgery (P＞0.05). But blood loss at 2 h and 24 h after surgery in the observation group were less than those in the control group, with statistically significant differences (P＜0.05). The measurement values of RBC, HGB and HCT in observation group were significantly higher than those in control group, with statistically significant differences (P＜0.05). The total incidence of postoperative complications in observation group was significantly lower than that in control group, with a statistically significant difference (P＜0.05). Conclusion Evidence-based nursing intervention can effectively reduce postpartum hemorrhage and postoperative complications of cesarean section women.