Leukemia is the most common malignant neoplastic disease of the hematological system. Due to the massive and disorderly proliferation of leukemia cells in the bone marrow, the normal hematopoietic function is destroyed and the patient will experience a series of symptoms, among which bleeding is more obvious. In general, the early stage of leukemia is relatively mild, and the bleeding points are mostly located in the extremities, especially in the lower extremities, and are symmetrically distributed. The bleeding spots are usually pinpoint in shape and purplish red in color. If the disease is more severe and combined with coagulation disorders, the patient may have bleeding symptoms in the forehead, back, face and other areas in addition to the extremities, and sometimes even large petechiae may appear. This often means that the patient is at significantly increased risk of bleeding and is prone to internal bleeding, which can manifest as vomiting blood, black stool, blood in urine, etc. The most serious case is the occurrence of intracranial bleeding. Patients show headache, nausea, vomiting, coma, and even cause clinical death.