Objective:To determine the expression of interleukin(IL)-23 and its influence on the associated cytokines and genes in different immune phases of chronic hepatitis B (CHB) patients.Methods:Our study included 197 patients with chronic hepatitis B(including 16 for immune tolerance phase, 106 for immune clearance phase, 59 for immune control phase and 16 for reactivation phase). The level of IL-23、IL-17、TGF-β、IL-10、IL-21 in plasma was detected by enzyme-linked immunosorbent assay (ELISA). The mRNA expression level of ROR-γt、Foxp3 was detected by real time quantitative PCR (RT-qPCR). The data were analyzed with IBM SPSS Statistics 23.0 software.Results:The level of IL-23、IL-17、IL-21、ROR-γt mRNA in CHB patients is significantly higher than normal controls ( P<0.05). The level of IL-23 is positively correlated with ALT、AST、GGT、TBil、IL-17、IL-21 in plasma and ROR-γt mRNA、Foxp3 mRNA level in PBMCs( P<0.05). The expression of IL-23、IL-17 and ROR-γt mRNA are different between different immune phases( P<0.05). Conclusions:IL-23 might play an important role on the different immune phases in chronic HBV infection through influencing associated cytokines and genes.