This study examined the properties of ultra-microporous carbon synthesized by the pyrolysis of poly(vinylidene fluoride) as a function of the heat-treatment temperature, and evaluated the CO 2 adsorption capacity by pressure swing analysis. X-ray photoelectron spectroscopy confirmed the specific elements of the heat-treated carbon (HTC) surfaces. The textural properties were analyzed using N 2 adsorption isotherms at 77K. The CO 2 adsorption capacity was measured by CO 2 isothermal adsorption at 298K and under increasing pressure up to 100kPa. The CO 2 adsorption capacity increased with increasing heat-treatment temperature to 873K (HTC-873, 155mg/g), and then decreased at 973K (HTC-973), which correlated with their micropore volume. Interestingly, HTC-773 with a smaller pore size had higher CO 2 adsorption capacity than HTC-873 at pressures up to 30kPa. This results show that the CO 2 adsorption capacity at a certain pressures (in particular <30kPa) is strongly affected by the pore size of the HTC samples but not by the micropore volume or specific surface area.