Abstract This retrospective study aimed to stress the advantages of autologous hematopoietic stem cell transplantation (auto-HSCT) in treating primary MM. Ninety-four MM patients who underwent initial parallel sequential auto-HSCT were selected. Data on efficacy (efficacy evaluation, renal function and hemoglobin recovery), immune reconstitution (B-cell subsets, immunoglobulin levels, T-cell subsets, NK cells, neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR)) and hematopoietic reconstitution times were collected and analyzed. Whether in all selected patients or in groups R-ISS II-III, there was a notable increase in the proportion of patients achieving in a very good partial response (VGPR) or better (P