Copper oxide modified activated carbon (CuO/AC) composites for the CO2 capture were synthesized via a facile assembly strategy associated with a direct solid-state heat dispersion process by introducing CuO into AC using Cu(NO3)2 as the copper source. The synthesized CuO/AC composites with various CuO contents were characterized by powder X-ray diffraction, scanning electron microscopy and nitrogen adsorption-desorption measurement, and the CO2 adsorption performance was investigated. The characterization results indicate that the Cu(NO3)2 species was well dispersed into the AC pore channels and then converted to a highly dispersed CuO after the activation process. The adsorption results reveal that the CO2 adsorption performance can be significantly improved by introducing CuO onto the AC surfaces, and the CuO(0.6)/AC composite with a CuO loading of 0.6mmol/g AC shows a high CO2 adsorption capacity and adsorption selectivity and displays an excellent reversibility. Additionally, the calculated adsorption heat values of CO2 on the CuO(0.6)/AC composite are in the range of 27.3 to 33.9 kJ/mol.