Abstract: OBJECTIV To observe the influence of vacuum sealing drainage (VSD) on control of infections and foot microcirculation state of patients with composite tissue defect of lateral malleolus so as to understand the application value of VSD in such group of patients. METHODS A total of 58 patients with composite tissue defect of lateral malleolus who were treated in the hospital from Mar 2015 to Jun 2016 were recruited as the study objects and randomly divided into two groups. The control group with 29 cases was given conventional therapy for the composite tissue defect of lateral malleolus, while the observation group with 29 cases was treated with additional VSD on the basis of the treatment of the control group. The incidence of infection of the two groups of patients was statistically analyzed, and the related indexes of foot microcirculation state (nailfold microcirculation and hemorheology) were observed and compared between the two groups of patients before and after the treatment. RESULTS The infection rate of the observation group was 3.45%, significantly lower than 13.79% of the control group. The related indexes of foot microcirculation state (nailfold microcirculation and hemorheology) of the observation group were significantly better than those of the control group after the treatment (P＜0.05). CONCLUSION The VSD can achieve significant effect on control of infection in the patients with composite tissue defect of lateral malleolus and has more positive influence on the foot microcirculation state, and it has high application value in this group of patients.