Multiple myeloma（MM）is a malignant clonal cancer of plasma cell characterized by overpro⁃ duction of abnormal plasma cells in the bone marrow and skeletal destruction. Its incidence rate ranks the second among all malignant hematologic diseases. With a widespread usage of protease inhibitors，immunomodulators， corticosteroids and other chemicals，the survival rate of MM has substantially improved in the past 20 years. Corti⁃ costeroids are the first⁃line drug of MM combination chemotherapy，but almost all MM will relapse or become drug resistance in later treatment. There fore，exploring the mechanism of MM′s drug resistance to corticosteroids and enhancing MM′s sensitivity to dexamethasone will provide a a improved treatment plan to the patients prognosis and deeper understanding of MM.