Abstract: The composition and pore-characterization of char from pyrolysis of used tires were determined in this paper. Three oxidizing agents were used for the activation of carbonized char, including steam, CO2 and 2％ O2 in nitrogen. Char-activation with CO2 was conducted primarily. The activated char can get a great surface area, which can be used to handle organic elding and textile industry waste. The result shows that the content of ashes and sulfurs in the pyrolysis char is pretty high and there is a maximum pore volume at the pore radius of about 25 nm. At the condition of same activation time and gas flow rate, the higher the temperature is, the larger the burn-off rate and the surface area are. Also, at the condition of the same temperature and gas flow rate, the longer activated time is, the larger burn-off rate and BET are. For all activation experiments, the higher burn-off rate would result in larger surface area. The activation effect with steam and CO2 is better, and followed by that with 2％ O2 in nitrogen. By the comparison of activated char and commercial activated carbon, the former has a profound pore-characterization and it has a potential to substitute commercial activated carbons for the macromolecular absorption.