〔Abstract〕 Objective To investigate the expression of cell division cycle protein 27 gene(cdc27) on peripheral blood mononuclear cell(PBMC) from systemic lupus erythematosus(SLE) patients and its significance. Methods The expression of cdc27 on PBMC from 32 SLE patients and 21 healthy controls(HC) was examined by reverse transcription-polymerase chain reaction(RT-PCR). The expression of cdc27 on PBMC was compared between SLE patients and HC. Correlations of cdc27 on PBMC with several clinical indexes were analyzed. We also analyzed regular treatment influence on expression of cdc27. Moreover, the receiver operating characteristic(ROC) was used to analyze the diagnostic value of cdc27. Results The expression of cdc27 on PBMC in SLE patients was significantly lower than that in HC(U=126.0,P<0.001). The expression of cdc27 on PBMC in SLE patients was negatively correlated with CRP(r s =-0.462,P=0.009),ESR(r s =-0.358,P=0.048),monocytes numbers(r s =-0.386,P=0.029). The expression of cdc27 on PBMC in SLE patients was significantly increased after effective treatment(P=0.005). The area under ROC curve(AUC), sensibility and specificity of cdc27 on PBMC between SLE patients and HC were 0.813(95%CI:0.681～0.944;P<0.001), 81.25%, 80.95%. Conclusion The expression of cdc27 on PBMC is decreased in SLE patients and correlated with inflammation and treatment. This study suggests that the cdc27 on PBMC may be a potential diagnosis biomarker of SLE patients.