Abstract: OBJECTIVE To compare the clinical efficacy and safety of ticagrelor and aspirin in the prevention of stroke recurrence in patients with acute stroke or transient ischemic attack. METHODS Patients with acute stroke or transient ischemic attack were included in this study within 24 h of clinical symptoms of stroke and assigned to receive ticagrelor or aspirin treatment. The primary endpoints included recurrent stroke, cardiovascular events, or all-cause death and the secondary endpoints included incidence of fatal bleeding, mild bleeding, and dyspnea were observed. RESULTS A total of 1 307 patients were enrolled in this study, 651 in the ticagrelor treatment group and 656 in the aspirin treatment group. During the 90 d treatment, 47 patients(7.2%) had primary endpoints in the ticagrelor treatment group, 38 of which had recurrent ischemic stroke(5.9%). In contrast, 52 patients(7.9%) had primary endpoints in the aspirin treatment group, of which 44 cases were ischemic stroke(6.8%). So treat with ticagrelor could significantly reduce the rate of stroke relapse of stroke(P=0.03). A total of 51(7.8%) patients occurred secondary endpoints in the ticagrelor treatment group, including 8 cases of mild bleeding(1.3%), and 40 cases of dyspnea(6.2%). In aspirin treatment group, 17 patients(2.6%) had secondary endpoint events, of which 4 cases were minor bleeding(0.6%) and 9 cases were dyspnea(1.4%). So the incidence of mild bleeding and dyspnea was significantly higher in ticagrelor treatment group than in aspirin treatment group. CONCLUSION For patients with acute stroke or transient ischemic attack, ticagrelor has a better therapeutic effect than aspirin, which can significantly reduce the recurrence rate of stroke and improve the prognosis of patients.