Abstract: Objective To explore the value of laboratory tests for the diagnosis of multiple myeloma. Methods The clinical data of bone marrow cell morphology, serum protein electrophoresis, immunoelectrophoresis and immunoglobulin in one patient with multiple myeloma were reviewed and analyzed. Results Immunoglobulin type conversion was seen in the patient following autologous hematopoietic stem cell transplantation. Conclusion The comprehensive laboratory tests may help to reduce the frequency of misdiagnosis of multiple myeloma. The changes of immunoglobulin type is of great significance for the clinical diagnosis and treatment of multiple myeloma.

Key words: Multiple myeloma, Immunoglobulin type conversionn, Laboratory examination