A comparison of Methylene Blue adsorption by 3 types of activated carbons(activated carbon fiber, granulated activated carbon, and powder activated carbon)was investigated. The specific surface area, average pore diameter, pore distribution of each activated carbon were measured by BET adsorption apparatus. The result showed that the specific surface area of 1156m(2)/g and 630m(2)/g for activated carbon fiber and powder activated carbon, rspectively. Methylene Blue absorbance was measured using UV spectophotomether by weight basis and surface basis for each of the activated carbon. The rate of Methylene Blue adsorption by activated carbon fiber was the fastest amount the 3 types in al of the cases studied.