In general, stem cell therapy is also known as hematopoietic stem cell transplantation therapy. Hematopoietic stem cell transplantation therapy can treat many hematologic diseases, especially most hematologic malignant diseases. With hematopoietic stem cell transplantation therapy, it is possible to cure malignant diseases. In patients with acute leukemia, except for acute promyelocytic leukemia, the only type of acute leukemia that can be completely cured is hematopoietic stem cell transplantation therapy, other chemotherapy methods are not able to completely cure and patients have a high relapse rate. For patients with lymphoma or multiple myeloma, autologous hematopoietic stem cell transplantation can be applied to treat the patient, which can significantly prolong the patient’s survival and even achieve a cure. In addition, certain autoimmune diseases, such as systemic lupus erythematosus, have also been cured by stem cell transplantation. Thalassemia can also be cured by applying hematopoietic stem cell transplantation. Stem cell transplantation can treat a variety of hematologic diseases, while other non-hematologic diseases may also be cured by stem cell therapy.