Abstract: In order to improve and enhance the adsorption selectivity and adsorption capacity of nano cellulose (CNF) aerogels on CO₂, The spherical hydrogels prepared were graft modified with 3 -(2-aminoethylamino) propylmethyldimethoxysilane as modifier, and then freeze-dried to prepare amino-modified CNF aerogels. The aerogels were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, specific surface area porosimeter, and conduct CO₂ adsorption/desorption test. The results showed that the adsorption capacity of modified CNF aerogels increased with the increase of nitrogen content. When the initial pressure is 0.13 MPa and the temperature is 20 ℃, the maximum CO₂ adsorption capacity is 1.80 mmol/g, which is much larger than that of unmodified CNF aerogels. After 10 adsorption/desorption cycles, its adsorption capacity is basically stable with good regeneration capacity.