Abstract: In order to gain an insight into the adsorption property of coal-based activated carbon, the low-ash anthracite sample first goes through immersion in KOH solution, and is then put into tubular oven for activating treatment, and is finally cleaned with 5%(by mass)hydrochloride solution and deionized water.Following an analysis of the phase, pore structure and form and appearance of the activated carbon using XRD, SEM and BET technologies, themechanism of adsorption of the carbon is investigated through methylene blue test.Test result indicates that:the pore volume and adsorption rate of the carbon tend to increase with the increase of KOH/carbon ratio and concentration of KOH solution; with a KOH/carbon ratio of 2∶1, a concentration of KOH of 0.20 g/mL and an activating temperature of 750 ℃, the total pore volume is up to 1 356 m²/g, with an average pore size of around 2 nm and a proportion of micropores reaching 65.563%'and the adsorption of coal-based activated carbon of methylene blue(MB) is a process which conforms to the pseudo-second-order dynamic process and the Freundlich isothermal adsorption model.