Objective: To evaluate the influence of thromboelastography-guided hemostatic algorithm on allogeneic transfusion requirements during pediatric hemispherectomy. Methods: Clinical data of 38 children who underwent hemispherectomy from January 1, 2011 to October 31, 2023 at Xuanwu Hospital of Capital Medical University were retrospective collected. Patients were divided into study group (n=17) and control group (n=21) according to whether thromboelastography was employed to guide hemostatic algorithm. Demographic data and surgical data were recorded. The primary outcomes were allogeneic transfusion rates, including RBC transfusion rate, plasma transfusion rate, and platelets transfusion rate. The second outcomes were estimated blood loss, postoperative seizures during hospitalization, thromboembolic events, and length of hospital stay. Results: There were 13 boys and 4 girls with mean age of (5.7±3.3) years old in study group, and 16 boys and 5 girls with mean age of (7.4±3.4) years old in control group. The surgery duration, anesthesia duration and the proportion of prophylactic administration of tranexamic acid in study group were (424.5±98.5) min, (542.8±106.9) min, and 94.1% (16/17), which were higher than (353.1±85.3) min, (445.3±87.9) min, and 47.6% (10/21) in control group (all P<0.05). The rates of intra- and perioperative allogeneic plasma transfusion in study group were 52.9% (9/17) and 64.7% (11/17) respectively, which were lower than 90.5% (19/21) and 95.2% (20/21) in control group (all P<0.05). The ratio of fibrinogen concentrates administration in study group was 58.8% (10/17), which was higher than that in control group [4.8% (1/21), P=0.001]. There were no statistically differences in intra- and perioperative allogeneic RBC transfusion rates between the two groups (all P>0.05). No platelets were transfused in both groups. There were no statistically differences in estimated blood loss, postoperative seizures during hospitalization and the length of hospital stay between the two groups (all P>0.05). No postoperative thromboembolic events were observed. Conclusion: Thromboelastography-guided hemostatic algorithm can reduce allogeneic plasma transfusion requirements but not RBC transfusion requirements during pediatric hemispherectomy.