The steps of hematopoietic stem cell transplantation include: collection of hematopoietic stem cells, pre-transplantation recipient pretreatment, transplantation of hematopoietic stem cells, and postoperative care. 1. Collection of hematopoietic stem cells. Allogeneic stem cell transplantation or autologous stem cell transplantation can be chosen according to the patient’s disease. The doctor collects peripheral blood from the donor with the required number of stem cells and collects the stem cells from it, and then freezes and stores them for use. 2. Recipient pretreatment. Before transplantation, the patient can be pretreated with high-dose radiotherapy and chemotherapy, and at the same time, the patient is moved into a sterile isolation ward. 3. Transplantation of hematopoietic stem cells. The hematopoietic stem cells prepared in advance are fed into the patient by intravenous infusion, while the patient continues to be observed in the isolation ward. 4. Postoperative care. The main purpose is to prevent and treat postoperative complications such as infection.