Adsorption equilibrium data for CO2 and N2 on coal-based activated carbon were obtained at 323.15, 348.15, 363.15 K and at partial pressures from 100 Pa to 82425 Pa by a volumetric apparatus. Lower temperature is helpful for the adsorption. It was observed the saturation loadings at 323.15 K are 0.3 mmolg-1, 0.057mmolg-1 for CO2 and N2, respectively. The Langmuir and Sips equations were used to correlate the experimental data. It was found that the Sips equation is more accurate to describe the adsorption behavior of both gases on activated carbon. Henry’s constant was calculated, it proves that activated carbon has a high selectivity on CO2 than N2, the maximum separation index is 5.5.