To compare the effects of ticlopidine and ligustrazine on platelet agglutination in patients with ischemic cerebral infarction.Methods:Turbidimetric method was utilized to measure platelet agglutination.Results:Both ticlopidine and ligustrazine can evidently inhibit platelet aggregation.Ticlopidine has a slightly better effect than ligustrazine in inhibiting platelet aggregation,however the difference did not reach statistical significance( P >0 05).Conclusion:Both Ticlopidine and ligustrazine are effective drugs in inhibiting platelet aggregation,but ligustrazine is much cheaper.