Multiple myeloma (MM) is a malignant disease of plasma cells, and autologous hematopoietic stem cell transplantation (ASCT) can improve remission and survival rates in MM. With the use of new drugs, the status of ASCT is being challenged. Which patients are suitable for transplantation and what is the timing of transplantation remains controversial. How to choose induction therapy before transplantation, maintenance and consolidation therapy after transplantation. How stem cell mobilization protocols and pretreatment protocols are evaluated. The attached PTT is the content of the departmental business study for all patients.