The objective of this study was to investigate the diagnostic significance of serum protein electrophoresis and immunofixation electrophoresis detection in diagnosis of multiple myeloma (MM). One hundred and five patients were investigated. The detection rate of M protein by immunofixation electrophoresis detection was better (105 cases, 100%) than that of serum protein electrophoresis (101 cases, 96.19%, p<0.001). The M band was not detected by serum protein electrophoresis in four cases (3.81%), among which one case (0.95%) was identified as IgA type and 3 cases (2.86%) as light chain type after immunoglobulin analysis. Immunofixation electrophoresis detection technique can be used for screening M protein in patients with atypical MM; and immunofixation electrophoresis detection technique can increase the diagnosis accuracy in patients with atypical MM.