AIM To investigate the levels, ratios, and clinical significance of T helper 17(Th17) cells and regulatory T(Treg) cells in the peripheral blood of patients with autoimmune liver disease(AILD). METHODS F o r t y-t w o A I L D p a t i e n t s w e r e i n c l u d e d i n t h e experimental group(group E), and 11 healthy subjects were recruited as the control group(group C). Flow cytometry was performed to determine the percentages of Th17 and Treg cells in peripheral blood lymphocytes. Furthermore, a range of biochemical indices was measured simultaneously in the blood of group E patients. RESULTS The percentage of Th17 cells and the Th17/Treg ratio were higher in group E than in group C(P < 0.01), whereas the percentage of Tregs was lower in the group E patients(P < 0.05). Patients in group E who were admitted with AILD in the active stage showed significantly higher Th17 percentages and Th17/Treg ratios than those measured in patients with AILD in remission(P < 0.05). In addition, among patients with AILD in the active stage, individuals that remained unhealed after hospitalization showed significantly higher baseline values of the Th17 percentage and the Th17/Treg ratio than those detected in patients who improved after treatment(P < 0.05). The results suggested that imbalance in the Th17/Treg ratio plays an important role in the pathogenesis and development of AILD.CONCLUSION A high Th17/Treg ratio appears to predict poor shortterm prognosis in patients with AILD in the active stage. AIM To investigate the levels, ratios, and clinical significance of T helper 17 (Th17) cells and regulatory T (Treg) cells in the peripheral blood of patients with autoimmune liver disease (AILD). METHODS Fortyt wo AILD patientswereincludedi nthe experimental group (group E), and 11 healthy subjects were recruited as the control group (group C). Flow cytometry was performed to determine the percentages of Th17 and Treg cells in peripheral blood lymphocytes. Furthermore, a range of biochemical indices was measured simultaneously in the RESULTS The percentage of Th17 cells and the Th17 / Treg ratio were higher in group E than in group C (P <0.01), while the percentage of Tregs was lower in the group E patients (P <0.05) . Patients in group E who were admitted with AILD in the active stage showed significantly higher Th17 percentages and Th17 / Treg ratios than those measured in patients with AILD in remission (P <0.05). In addition, amon g patients with AILD in the active stage, individuals that remained unhealed after hospitalization showed significantly higher baseline values ​​of the Th17 percentage and the Th17 / Treg ratios than those detected in patients who improved after treatment (P <0.05). The results suggested that imbalance in the Th17 / Treg ratio plays an important role in the pathogenesis and development of AILD. CONCLUSION A high Th17 / Treg ratio appears to predict poor shortterm prognosis in patients with AILD in the active stage.