ObjectiveIn addition to the surface hemorrhage of cancellous bone after large‐area osteotomy, the intramedullary hemorrhage after the reamed knee joint is also a major cause of postoperative bleeding after total knee arthroplasty (TKA). This study evaluated the efficacy and safety of bone wax application at different time points of prone hemorrhage to reduce perioperative blood loss.MethodsFrom August 2023 to December 2023, 150 patients undergoing primary unilateral TKA were included in this prospective, randomized controlled trial, patients were randomly divided into three groups: group A, after autogenous osteotomy plug was used to fill the femoral medullary cavity, the residual space was sealed with bone wax and the exposed cancellous bone surface around the prosthesis was coated with bone wax after the prosthesis adhesion; group B, only the exposed cancellous bone surface around the prosthesis was coated with bone wax; and group C, no bone wax was used. The primary outcome was total perioperative blood loss. Secondary outcomes included occult blood loss, postoperative hemoglobin reduction, blood transfusion rate, lower limb diameter, and knee function, while length of hospital stay was recorded. Tertiary outcomes included the incidence of postoperative related adverse events.ResultsThe total blood loss in group A (551.5 ± 224.5 mL) and group B (656.3 ± 267.7 mL) was significantly lower than that in group C (755.3 ± 248.3 ml, p < 0.001), and the total blood loss in group A was also lower than that in group B (p < 0.05). There were also significant differences in the reduction of hemoglobin level and hidden blood loss among the three groups (p < 0.05). However, there was no significant improvement in postoperative lower limb swelling, knee joint activity and hospitalization time; there was no significant difference in the incidence of complications such as thromboembolism.ConclusionThe use of bone wax in TKA can safely and effectively reduce perioperative blood loss and hemoglobin drop rate, and multiple use at time points during the operation when blood loss is prone to occur can produce more significant hemostatic effect.