Charcoals were derived from cotton stalk pyrolysis in a fixed-bed reactor at different temperatures (400℃, 600℃, 800℃, the samples are labeled as CS—400, CS—600, CS—800, respectively). The charcoals were characterized by elemental analysis, nitrogen adsorptiondesorption isotherms, Boehm titration and Fourier-transform infrared spectroscopy. The results show that cotton stalk charcoal obtained at 400℃ has a large number of organic groups on its surface and poor pore structure. With the increase of pyrolysis temperature, oxygenic organics in cotton stalk decompose further, which leads to the reduction of acidic functional groups on charcoals surface, and the increase of the pyrone structures of the basic groups, meanwhile, pore structure is improved significantly and the surface area is increased, especially for the micropores. The H/C mole ratio, surface acid and basic functional groups of cotton stalk charcoals are the main factors that influence the removal efficiency of furfural. The increase of pyrolysis temperature promotes removal of furfural onto cotton stalk charcoal. With the increase of carbonization degree, the basic functional groups increase, while the acidic functional groups decrease, which results in the increase of π—π dispersion between the surfaces of cotton stalk charcoals and furfural molecular, therefore the best removal efficiency of furfural is obtained by cotton stalk charcoal pyrolyzed at 800℃.