Background : Mesoglycan, a preparation of natural glycosaminoglycans, has pleiotropic protective effects on cerebral vasculature, including anti-thrombotic, fibrinolytic and anti-atherogenic activity. It also has shown a feasible potential in the secondary prevention for cerebral ischemia, In this study. we investigated the effect of mesoglycan and aspirin combination on fibrinogen levels in patients with previous ischemic stroke. Methods : Patients with previous ischemic stroke were randomly assigned as either mesoglycan group (mesoglycan 50mg twice daily + aspirin 300mg once daily) or control group (placebo twice daily + aspirin 300mg once daily), and treated in double-blinded manner. Efficacy variable included the fibrinogen level, which was checked on every visit for 8 weeks (at the second, forth and eighth week). Results : Forty-five outpatients (22 control group and 23 mesoglycan group) were included and analyzed. There was no significant difference in the baseline characteristics, including age, sex, baseline fibrinogen and cholesterol profiles, between the mesoglycan group and the control group, No clinical or laboratory adverse effects were reported in the mesoglycan group, while two non-treatment emerging adverse effects were reported in the control group. Mesoglycan group exerted no significant change of the fibrinogen level compared with the control group. Conclusions: In this study, mesoglycan and aspirin combination in patients with previous cerebral ischemia showed a favorable tolerability without any adverse effects. However, to verify the efficacy of mesoglycan and aspirin combination on the fibrinolytic system or the secondary prevention, further study is warranted based on a larger scaled subjects and long-term period.