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As a typical two-dimensional (2D) MXene, Ti₃C₂O₂ has been considered as a potential material for high-performance hydrogen evolution reaction (HER) catalyst, due to its anticorrosion and hydrophilic surface. However, it is still a challenge to improve the Ti₃C₂O₂ surficial HER catalytic activity. In this work, we investigated the HER activity of Ti₃C₂O₂ after the surface was doped with S, Se, and Te by the first principles method. The results indicated that the HER activity of Ti₃C₂O₂ is improved after being doped with S, Se, Te because the Gibbs free energy of hydrogen adsorption (ΔG_H) is increased from −2.19 eV to 0.08 eV. Furthermore, we also found that the ΔG_H of Ti₃C₂O₂ increased from 0.182 eV to 0.08 eV with the doping concentration varied from 5.5% to 16.7%. The HER catalytic activity improvement of Ti₃C₂O₂ is attributed to the local crystal structure distortion in catalytic active sites and Fermi level shift leads to the p-d orbital hybridization. Our results pave a new avenue for preparing a low-cost and high performance HER catalyst.