Petechiae in patients with coronary artery disease may be related to oral antiplatelet drugs, and some patients may have hematologic disorders. Patients with coronary artery disease need to take oral antiplatelet drugs, commonly used drugs are aspirin, clopidogrel, tegretol and other drugs, acute myocardial infarction and stenting patients need to take two oral antiplatelet drugs to increase the antiplatelet aggregation, to avoid the aggravation of coronary artery disease or the formation of in-stent thrombosis. The main adverse reaction of antiplatelet drugs is bleeding, skin mucosa is generally more common, patients can also occur nosebleeds, gum bleeding, a few patients will occur intracranial hemorrhage. Coronary heart disease patients appear subcutaneous petechiae should also consider the possibility of blood diseases, such as leukemia, thrombocytopenia, etc., the symptoms are obvious to the hospital in a timely manner, under the guidance of the physician to clarify the diagnosis.