Abstract: Zeolite molecular sieves have been widely applied in the field of adsorption and separation of CO₂. Three common zeolite molecular sieves 5A, 13X, and NaY were selected to study the adsorption performance of CO₂. The effects of pore structure parameters, adsorption pressure, and adsorption heat on the adsorption performance of CO₂ were investigated, and results reveal that all three adsorbents belong to microporous adsorbents, and the adsorption of CO₂ at normal temperature is physical adsorption. The greater the adsorption pressure, the greater the static adsorption capacity. The order of the static adsorption capacity of the three adsorbents is NaY > 5A > 13X, and the size of the static adsorption capacity is related to the pore structure parameters and adsorption coefficient b of the adsorbents. The larger the pore structure parameters (pore volume, pore size, specific surface area) and the larger the value of coefficient b, the larger the adsorption capacity of the adsorbents. The order of CO₂ breakthrough adsorption capacity and equilibrium adsorption capacity of the three zeolites is 13X > 5A > NaY, and there is no obvious relationship between static adsorption capacity and dynamic adsorption capacity. Zeolite NaY exhibited the best dynamic adsorption cycle stability among the zeolites. Compared with 5A and 13X, whose adsorption capacity decreases by 74% and 68%, respectively, NaY only decreases by 29% after five cycles of adsorption and desorption. In addition, NaY has the smallest adsorption heat and weak adsorption effect with CO₂, making desorb easier.