OBJECTIVE： To investigate the effects of Xuesaitong for injection on microembolic signal （MES） and blood lipid of patients with middle cerebral artery （MCA）atherosclerotic stenosis complicated with MES positive transient ischemic attack （TIA）. METHODS： A total of 98 patients with MCA atherosclerotic stenosis complicated with MES positive TIA in the Affiliated Hospital of Chengdu University of TCM during May 2015-May 2016 were divided into routine group and Xuesaitong group  according to random numble table， with 49 cases in each group. Routine group received routine treatment. Xuesaitong group was additionally given Xuesaitong for injection （lyophilized） 400 mg intravenously， once a day， for consecutive 15 d， on the basis of routine treatment. The distribution of MES classification and the number of MES were observed in 2 groups before treatment， 15 d after treatment and 3rd and 6th month after treatment. The levels of TG， TC， LDL were observed before treatment and 15 d after treatment. The occurrence of ischemia event and ADR were recorded. RESULTS： Fifteen days after treatment， the distribution of MES classification in 2 groups was significantly better than before treatment； Xuesaitong group was significantly better than routine group， with statistical significance （P＜0.05）. At 3rd and 6th month after treatment， the distribution of MES classification in Xuesaitong group was significantly better than routine group； 6th month after treatment was significantly better than 3rd month  after treatment， with statistical significance （P＜0.05）. Fifteen days and the 3rd， 6th month after treatment， the number of MES in 2 groups were significantly lower than before treatment and decreased as time； Xuesaitong group was significantly lower than routine group， with statistical significance （P＜0.05）. Fifteen days after treatment， TG and TC levels of 2 groups were significantly lower than before treatment； Xuesaitong group was significantly lower than routine group， with statistical significance （P＜0.05）； there was no statistical significance in the level of LDL before and after treatment （P＞0.05）.  The incidence of ischemic events in routine group at 6th month after treatment was significantly higher than 3rd month after treatment， and the incidence of ischemic events in Xuesaitong group at 3rd and 6th month after treatment was significantly lower than routine group， with statistical significance （P＜0.05）. At 6th month after treatment， the incidence of ADR in 2 groups was significantly lower than 3rd month， with statistical significance （P＜0.05）. CONCLUSIONS： Based on routine treatment， Xuesaitong for injection can reduce the number of MES， reduce the incidence of ischemia events and further improve the level of blood lipid in patients with MCA atherosclerotic stenosis complicated with MES positive TIA without increasing the occurrence of ADR.