In the past 10 years, the treatment of multiple myeloma has made rapid progress, and the median survival time of patients has improved from about 3 years previously to 5-7 years, and even to more than 10 years in some patients. However, all patients have the possibility of recurrence, so how to detect recurrence early, and when to treat aggressively and when to simply observe closely or give palliative care? First, it is very important to review regularly when in remission, usually once every 2-3 months. Second, if there is an increase in the index, discuss carefully with your doctor whether immediate treatment is needed. If immediate systemic treatment is needed, consider applying the original effective regimen or a regimen containing new drugs, or adding other drugs with a different mechanism of action to the original regimen. If available, secondary autologous hematopoietic stem cell transplantation may be performed or entered into clinical trials. At the same time, the adverse effects of previously treated drugs should be explained to the competent physician for early prevention to avoid interruption of treatment due to toxic side effects of drugs, which may affect the efficacy of treatment.