It is impossible to compare the safety of aspirin and clopidogrel one-sidedly, the safety of the drug and the patient’s tolerance, adverse reactions, the specific use of drugs need to comply with medical advice. Aspirin is a cyclooxygenase inhibitor with antipyretic and anti-inflammatory effects, low-dose aspirin can inhibit platelet aggregation and prevent thrombosis, which is suitable for the prevention of heart attack, stroke, pulmonary embolism and so on. Adverse reactions include gastrointestinal discomfort, bleeding, hepatic and renal impairment, allergy, etc. It is contraindicated in patients with abnormal hepatic and renal functions. Clopidogrel is a drug that inhibits platelet activation, interferes with platelet activation and inhibits platelet aggregation and adhesion. It is suitable for the treatment of heart attack, acute coronary syndrome, angina pectoris, adverse reactions include bleeding, thrombocytopenia, leukopenia, dyspepsia, etc. It is contraindicated in patients with severe liver function abnormalities and active bleeding. Aspirin and clopidogrel can be combined in the acute stage of heart attack and cerebral infarction, both have different scope of application and adverse reactions, and both are widely used in clinical application, so it is not possible to assess the advantages and disadvantages of their safety. The use of drugs, need to be under the guidance of professional doctors.