Abstract： Objective： To observe the clinical effect of the therapy of modified Taohong Siwu tang combined with rivaroxaban on the prevention and treatment of deep vein thrombosis(DVT) after hip and knee arthroplasty. Methods：A total of 90 patients who received the hip and knee arthroplasty were selected and divided into the control group and the observation group according to the random number table method， with 45 cases in each group. Both groups were treated with antiinfection， nutritional support， analgesia and rehabilitation treatment after operation. The control group was additionally treated with rivaroxaban tablets after operation， and the observation group was additionally treated with modified Taohong Siwu tang based on the treatment of the control group. Both groups were treated for 14 days. The incidence of DVT and complications were compared between the two groups；before and after treatment，the levels of high- shear whole blood viscosity，low-shear whole blood viscosity，plasma viscosity，D-dimer(D-D) and fibrinogen(FIB) were compared between the two groups. Results： The incidence of DVT was 6.67% in the observation group， lower that of 24.44% in the control group(P＜0.05). Seven and fourteen days after operation， the high- shear whole blood viscosity， low- shear whole blood viscosity，plasma viscosity，D-D and FIB levels in the two groups were decreased when compared with those one day after operation， and the above levels in the observation group were lower than those in the control group at the same period， differences being significant(P＜0.05). The incidence of postoperative complications was 13.33% in the observation group， lower than that of 33.33% in the control group(P＜0.05). Conclusion：The therapy of modified Taohong Siwu tang combined with rivaroxaban can effectively prevent and treat DVT after hip and knee arthroplasty，improve the hemorheology，inhibit the coagulation of blood，and reduce the incidence of postoperative complications.