Abstract: Objective To study the seroimmunological features of mutiplemyeloma(MM). Methods 28 serum samples of MM patients were analyzed by agarose gel electrophoresis and electrophoretic scanning, quantitative measurement of serum protein and immunoglubulins, and immunofixation electrophoresis. Results M bands appeared in 96.4%serum sample, in which IgG、 IgM appeared in γ zone and IgA appeared in β zone. The figure of immunofixation electrophoresis varied from types to types of MM, IgG, IgA, IgM and free light chain accounted for 46.4%, 21.4%, 17.9%and 10.7%respectively in all of the M protein. By classification of the light chain types, M proteins of IgG and IgM were mainly κ type, and the light chain types were λ type. Part of the concentration of immonoglobulin which contains monoclonal component increased significantly. Conclusions An overall consideration of the laboratory results from above methods is helpful in making a more accurate laboratory diagnosis for patients with multiple myeloma.