To evaluate the efficacy of uterine balloon packing combined with uterine compression suture for treating hemorrhage after caesarean section of pregnant women with gestational diabetes mellitus (GDM). Methods: 98 pregnant women with GDM and postpartum hemorrhage after caesarean section from January 2021 to January 2022 were selected retrospectively. These women were divided into two groups, which included 49 cases with uterine balloon tamping for hemostatic treatment in group A and 49 cases with uterine balloon tamping combined with uterine compression suture for hemostatic treatment in group B according to different methods of hemostasis. The hemostatic effectiveness and postoperative complications rate of the women were compared between the two groups. Results: The effective rate (95.9%) of the women in group B was significantly higher than that (69.4%) of the women in group A. The intraoperative blood loss (1357.0±105.0 ml), the total blood loss (210.0±66.0 ml, and the blood transfusion rate (85.7%) of the women in group B were significantly lower than those (1774.0±210.0 ml, 220.0±70.0 ml, and 98.0%) of the women in group A (all P＜0.05). The values of red blood cell, hemoglobin, and total protein of the women in the two groups after operation had all decreased to different degrees, and the coagulation time of the women in the two groups after operation had prolonged, but all of which of the women had no significant differences between the two groups (all P＞0.05). The incidences of postoperative infection (2.0%) and hemorrhagic shock (0) of the women in group B were significantly lower than those (6.1% and 2.0%) of the women in group A, but the total incidence (4.1%) of the women in group B had no significantly different from that (8.2%) of the women in group A (P=0.399). Conclusion: The operation of uterine balloon packing combined with uterine compression suture can effectively control hemorrhage after caesarean section of the pregnant women with GDM, without increase of complications.