Objective:To observe the pattern change of chemokine (C-X-C motif) ligand 12 (CXCL12)/C-X-C chemokine receptor type 4 (CXCR4) in systemic lupus erythematosus (SLE) by comparing the condition of SLE patients between pre-treatment and post-treatment.Methods:Peripheral blood mononuclear cells were obtained from 15 healthy controls and 8 first visit SLE patients before and after treatment. The expression of CXCR4, CD3, and CD19 on lymphocytes were detected by flow cytometry. CXCL12 concentration in serum was measured by enzyme-linked immunosorbent assay. For statistical analysis, the independent sample t test was used for independent samples of normally distributed data, the paired sample t test was used for paired samples of normally distributed data, the Mann-Whitney U test was used for independent samples of nonnormal distribution data, and the Wilcoxon test was used for comparison of related samples of non-normal distribution data. In the correlation analysis, Pearson correlation coefficient was used for data conforming to the normal distribution, and Spearman correlation coefficient was used for data not conforming to the normal distribution. Results:① The percentage of CXCR4 + lymphocyte subsets was significantly increased after treatment (90±7)% when compared with that before treatment (75±17)% ( t=-2.440, P<0.05). ② The mean fluorescence intensity of CXCR4 + lymphocyte subsets was significantly decreased after treatment [119.00(92.93, 142.50)] compared with that before treatment [177.00(130.75, 280.25)] ( Z=-2.100, P<0.05). ③ The plasma concentration of CXCL12 was significantly decreased after treatment (540±243) pg/ml when compared with that before the treatment (1 146±570) pg/ml ( t=3.219, P<0.05). ④ Moreover, there were significant correlations between the trends of the above three indicators after treatment. Conclusion:The proportion, the mean fluorescence intensity of CXCR4 + lymphocyte in peripheal blood subsets and the concentration of CXCL12 in plasma of first visit SLE patients are significantly changed after treatment. That suggests CXCL12/CXCR4 is closely associated with SLE.