Bone marrow transplantation is also known as hematopoietic stem cell transplantation. Based on the source of hematopoietic stem cells, bone marrow transplantation is divided into two categories: autologous bone marrow transplantation and allogeneic bone marrow transplantation. Whether it is autologous transplantation or allogeneic bone marrow transplantation, the patient has to be pretreated before transplantation, including two categories of clear marrow pretreatment and non-clear marrow pretreatment, so that the common symptoms of bone marrow transplantation are: a. Symptoms of infection, whether it is clear marrow transplantation or non-clear marrow transplantation, the patient will have obvious bone marrow suppression, the number of white blood cells and neutrophils is severely reduced, and most Patients will have obvious symptoms of infection, manifested as fever, lung infection, intestinal infection, etc. Second, the common symptom is rejection, especially after allogeneic bone marrow transplantation, due to the rejection of the recipient to the hematopoietic stem cells, the patient may show symptoms of intestinal tract, especially diarrhea is the most common. Third, a common symptom is graft-versus-host disease, which is a significant rejection of the recipient’s organs after the donor’s hematopoietic stem cells become viable and can affect the patient’s skin, liver, intestines, etc., causing a series of symptoms.