Objective To investigate the application effect of ixazomib in patients with multiple myeloma(MM).Method According to different treatment methods,69 MM patients were divided into control group(n=34)and observa-tion group(n=35).Patients in the control group received lenalidomide+dexamethasone treatment,while patients in the observation group received ixazomib combind with lenalidomide+dexamethasone treatment.The clinical efficacy,im-mune function indicators(CD4+,CD8+,CD4+/CD8+),serum indicators[M protein,β2-microglobulin(β2-MG),erythrocyte sedimentation rate],and incidence of adverse reactions were compared between the two groups.Result The total remis-sion rate in observation group was 57.14%,which was higher than 32.35%in control group,and the difference was statis-tically significant(P<0.05).After treatment,the levels of CD4+,CD4+/CD8+in both groups were higher than those before treatment,while the levels of CD8+were lower than those before treatment,the level of CD4+,and CD4+/CD8+in observa-tion group were higher than those in control group,while the level of CD8+was lower than that in control group,and the differences were statistically significant(P<0.05).After treatment,the levels of M protein,β2-MG and erythrocyte sedi-mentation rate in both groups were lower than those before treatment,the levels of M protein,β2-MG and erythrocyte sedi-mentation rate in observation group were lower than those in control group,and the differences were statistically signifi-cant(P<0.05).The total incidence of adverse reactions in observation group was 31.43%,which was not statistically sig-nificant compared to 41.18%in control group(P>0.05).Conclusion Ixazomib in the treatment of MM patients can im-prove the overall response rate,enhance the immune function,reduce serum markers,and is relatively safe.