Aspirin is a clinically used antiplatelet drug whose main therapeutic effect is to prevent cardiac and cerebrovascular events, i.e., cerebral infarction or heart attack. However, the bleeding risk of aspirin should not be ignored. Some people will experience bleeding from the skin and mucous membranes such as gum bleeding and nasal bleeding when aspirin is used, and gastrointestinal bleeding also often occurs if the patient has ulcers in the gastrointestinal tract. However, the most dangerous bleeding is intracranial bleeding. Recent studies have shown that the risk of intracranial bleeding is about 0.63%, which means that two out of 1000 people will experience intracranial bleeding, and since the risk of intracranial bleeding is the highest, attention should be paid to this aspect. The risk of bleeding from aspirin is also high for patients preparing for surgery and needs to be stopped one week before surgery to prevent excessive bleeding during surgery.