Objective To observe the clinical efficacy of ergometrine maleate combined with oxytocin in scar uterus and its influence on blood biochemical indicators. Methods A total of 80 cesarean section parturients admitted to our hospital from March 2021 to March 2024 were selected as the research subjects, and they were divided into control group (n =40) and observation group (n =40) by the random number table method. All parturients underwent cesarean section, and the control group was given oxytocin injection, while the observation group was given ergometrine maleate injection combined with oxytocin injection. The clinical indicators, blood biochemical indicators, scar condition and adverse reactions were compared between the two groups. Results The amount of blood loss during operation and at 2 and 24 h after partum in the observation group was less than that in the control group, and the duration of bleeding was shorter than that in the control group (P <0.05). After operation, the Hb, RBC and PLT in the observation group were better than those in the control group (P <0.05). The scar recovery and scar healing in the observation group were better than those in the control group (P < 0.05 ). The incidence of adverse reactions in the observation group was 5.00%, which was lower than 27.50% in the control group (P <0.05). Conclusion The combined use of ergometrine maleate and oxytocin in the scar uterus parturients can not only effectively reduce the amount of intraoperative and postpartum hemorrhage, shorten the bleeding time, but also improve the blood circulation of patients, reduce scar formation and reduce the incidence of adverse reactions. The application value is high.