Multiple myeloma (MM) is a hematologic malignancy involving plasma cells, accounting for about 10 % of hematologic malignancies, and is currently the second most common hematologic tumor. Although the prognosis of patients with MM has been greatly improved by the development of new drugs and immunotherapies, there is still no cure, and most patients will develop refractory/relapsed MM (R/RMM) [1,2]. Natural killer (NK) cells are a class of innate immune lymphocytes with powerful natural killer activity, which have the ability to recognize tumor cells and infected virus cells, directly attack these cells, and participate in the regulation of a variety of cellular immune responses [3]. The study found that the number and function of NK cells in MM patients were suppressed, resulting in reduced immune surveillance and clearance of myeloma cells [4]. Restoring or enhancing the killing effect of NK cells on myeloma cells is an important strategy for MM immunotherapy [5].