Background There were only 3 multiple myeloma (MM) cell lines established in China. In this study,we succeeded in establishing a novel MM cell line and analyzed its biological characteristics. Methods Mononuclear cells isolated from the peripheral blood (PB) and bone marrow (BM) of a patient with advanced MM (λ light chain type) were cultured in medium. Cell morphology was analyzed by Wright-Giemsa-staining and cytochemical staining,immunophenotyping by flow cytometry and cytogenetic analysis by chromosome RHG-banding technique. Quantitative fluorescent polymerase chain reaction (PCR) was used to detect Epstein - Barr virus (EBV) DNA. Results The established cell line could survive and proliferate in the presence of feeder cells or conditioned medium. The cells secreted λ light chain and were negative for EBV. The Wright-Giemsa-staining showed typical plasmablast or plasma cell morphology. The cytochemical staining of the cells showed the following reactivity patterns: positive for acid phosphatase,negative for myeloperoxidase. The immunoprofile of the cells was concordant with that of MM cells: positive for CD_ 10 ,CD_ 28 ,CD_ 38 ,CD_ 138 ,CD_ 56 ,CD_ 49d ,CD_ 44 ,CD_ 54 and CD_ 58 ,negative for CD_ 19 , CD_ 40 ,CD_ 95 ,CD_ 95L ,CD_ 34 ,CD_2 and CD_5. The cytogenetic analysis showed complex chromosome abnormality of i (1q+),8q+,13q+,i (17q),i (18q) and +M. There was no difference in morphology,immunophenotype and cytogenetics between cells from PB and BM. Conclusions An MM cell line secreting λ light chain named CZ-1 was established. The cells from both PB and BM have the same biological characteristics. Background There were only 3 multiple myeloma (MM) cell lines established in China. In this study, we succeeded in establishing a novel MM cell line and analyzed its biological characteristics. Methods Mononuclear cells isolated from the peripheral blood (PB) and bone marrow BM) of a patient with advanced MM (λ light chain type) were cultured in Wright-Giemsa-staining and cytochemical staining, immunophenotyping by flow cytometry and cytogenetic analysis by chromosome RHG-banding technique. Quantitative fluorescent polymerase The established cell line could survive and proliferate in the presence of feeder cells or conditioned medium. The cells secreted λ light chain and were negative for EBV. The chain reaction (PCR) was used to detect Epstein - Barr virus (EBV) DNA. Wright-Giemsa-staining showed typical plasmablast or plasma cell morphology. The cytochemical staining of the cells showed the following reactivity patterns: positi ve for acid phosphatase, negative for myeloperoxidase. The immunoprofile of the cells was concordant with that of MM cells: positive for CD_10, CD_28, CD_38, CD_138, CD_56, CD_49d, CD_44, CD_54 and CD_58 , negative for CD 19, CD 40, CD 95, CD 95L, CD 34, CD 2 and CD 5. The cytogenetic analysis showed complex chromosome abnormality of i (1q +), 8q +, 13q +, i (17q), i M. There was no difference in morphology, immunophenotype and cytogenetics between cells from PB and BM. Conclusions An MM cell line secreting λ light chain named CZ-1 was established. The cells from both PB and BM have the same biological characteristics.