CD161-expressing CD8+ T cells consist of mucosal associated invariant T (MAIT) cells with semi-invariant TCR usage and non-MAIT CD161+CD8+ T cells with polyclonal TCR repertoire. Although CD161+CD8+ T cells are enriched in liver and embrace HBV-specific T cells in chronic hepatitis B (CHB) patients, their roles in disease progression remain poorly understood. This study aims to decipher their profiling and dynamic changes during chronic HBV infection.Blood samples from 257 CHB patients and non-tumor liver specimens from 73 HBV positive patients were analyzed for CD161+CD8+ T cell characterization by flow cytometry, TCR repertoire determination, transcriptomic analyses and cell experiments.CD161+CD8+ T cells were increased and hyper-activated in patients, while positive correlation between CD161+CD8+ T cell ratio and HBV-DNA level suggested this was insufficient to control HBV replication. The overlaps of complementarity determining region 3 sequences supported the switch between CD161-CD8+ and CD161+CD8+ populations. Although CD161+CD8+ T cells were endowed with innateness phenotype and enhanced antiviral capacity, the population from patients had impaired Th1 cytokines production, and elevated IL-17 and granzyme B secretion. The increased CD161+CD8+ T cells and their elevated granzyme B secretion positively correlated with inflammation-associated liver injury. Hepatic CD161+CD8+ T cells exhibited neutrophil-related pathogenic potential, because they had elevated transcript signatures and pro-inflammatory cytokine production in neutrophil recruitment- and response-related pathways that consistently changed in injury liver.Our results highlight reduced antiviral potency but increased pathogenic potential of CD161+CD8+ T cells in CHB patients, supporting CD161 expression as a marker of pathogenic CD8+ T subset and the intervention target for liver injury.Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.