Abstract: Computational simulation, as a strong and valuable complement approach to experimental study, can play a significant role in hydrogen isotope separation nowadays. In this work, a systematic study was conducted on H₂O-H₂ catalytic exchange capability for hydrogen isotopes separation of HD/H₂O, DT/D₂O and HT/H₂O based on numerical modelling. The results indicate that the highest separation capability is obtained at 343 K, an optimum temperature for three systems. Additionally, the optimum temperatures decrease down to 323 K with increasing gas-liquid ratio up to 3.0, however, the HT/H₂O system show less dependence on temperature considering the lower reduction of the separation ability. The number of theoretical stages for HT/H₂O system is less than the other two ones as presenting best separation performance. The profile of hydrogen concentration along the column behaves differently for three systems under the technical conditions in this study.