〔Abstract〕 Objective To investigate the expression of programmed death 1(PD1) on CXCR5-CD4+T cells from the patients with rheumatoid arthritis(RA) and to analyze the clinical relevance to disease severity. Methods The expression of PD1 on CXCR5-CD4+T cells were examined from 82 RA patients and 46 healthy controls(HC) by the technique of flow cytometry. The expression of PD1 including mean fluorescence intensity(MFI) on CXCR5-CD4+T cells and percentage of PD1+CXCR5-CD4+T cells were compared between RA patients and HC. Moreover, its correlation with laboratory inspection was analyzed. Results (1) The percentage of PD1+CXCR5-CD4+T cells and the MFI of PD1 on CXCR5-CD4+T cells from RA patients were significantly elevated compared with HC(P<0.000 1,U=1 082;P<0.000 1,U=917.5).(2) The percentage of PD1+CXCR5-CD4+T cells in RA patients were positively associated with rheumatoid factors(RF)(rs=0.267 9,P=0.022 9), increased RF(rs=0.419,P=0.001 1), increased anti-cyclic citrullinated peptide(anti-CCP)(rs=0.260 7,P=0.040 7), the percentage of plasmablasts(rs=0.302 4,P=0.029 3), DAS28-ESR(rs=0.244 7,P=0.042 7).(3) The MFI of PD1 on CXCR5-CD4+T cells in RA patients were negatively with lymphocytes number(rs=-0.338 7,P=0.002 0), lymphocytes percentage(rs=-0.347 9,P=0.001 4), lymphocyte-to-monocyte ratio(rs=-0.263 7,P=0.017 4). The MFI of PD1 on CXCR5-CD4+T cells in RA patients were positively associated with neutrophil percentage(rs=0.304 7,P=0.005 4), neutrophilto-lymphocyte ratio(rs=0.341 1,P=0.001 8), platelet-to-lymphocyte ratio(rs=0.232 1,P=0.037 1), systemic immune inflammation index(rs=0.288 0,P=0.009 1), derived Neutrophil to lymphocyte ratio(rs=0.320 3,P=0.003 6), erythrocyte sedimentation rate(rs=0.259 5,P=0.019 3), patient visual analogue scale(rs=0.241 6,P=0.043 9). The MFI of PD1 on CXCR5-CD4+T cells from high active RA patients was significantly elevated compared with non-high active group(P=0.040 7,U=406.0). Conclusion The abnormal expression of PD1 on CXCR5-CD4+T cells are observed in patients with RA. Increased expression of PD1 on CXCR5-CD4+T cells are associated with the production of antibody, the percentage of plasmablasts, inflammation, and also disease activity.