Aim To investigate the clinical incidence rate of cerebral microbleed (CMB) in patients with acute ischemic stroke (AIS) after intervention of antithrombotic therapy; To analyze the possible risk factors and imaging characteristics of CMB. Methods On the basis of clinical evaluation after admission, all AIS patients were administered mono-antiplatelet therapy or dual-antiplatelet therapy. At the end of treatment, CMB situation was evaluated by magnetic susceptibility weighted imaging. The differences of clinical data were compared between CMB group and non CMB group. Results A total of 240 patients with AIS was included in this study, and 70 cases (29.17%) were complicated with CMB among the patients. In the CMB group, microbleed lesions were located in basal ganglia region (48 cases, 68.57%), cortical-subcortical region (41 cases, 58.57%), thalamencephalon (26 cases, 37.14%), brainstem (24 cases, 34.29%), and parencephalon (16 cases, 22.86%). The size of microbleed lesions ranged from 0 to 108 μm, average of 14.02±0.32 μm. There were significant difference in the age, drinking history, hypertension history, history of cerebral hemorrhage, systolic blood pressure and diastolic blood pressure of CMB group compared with non CMB group (P＜0.05). Conclusions Patients with AIS are prone to concurrent CMB after intervention of antithrombotic therapy, and clinicians should pay special attention to this.