Abstract: The paper prepared activated carbon ( AC) with high specific surface and considerable mesopores from peanut shell by microwave irradiation，and studied effects of the type of activators，impregnation time，impregnation ratio，the concentration of activators，microwave power and irradiation time on the adsorption capacity of AC． The results showed that: Peanut shell-based AC with zinc chloride activation had higher adsorption capacity compared with phosphoric acid and sodium hydroxide． Under the conditions of impregnation ratio of 80% zinc chloride and impregnation ratio of 1∶ 6，with microwave power of 500W for 6 min，the prepared carbons had the maximal adsorption rate，and the adsorption property on methylene blue and iodin of the peanut shellbased ACs were ( 898. 6 ±12. 8) mg/g and ( 46. 2 ± 3. 8) mg/g，respectively． The experiment also revealed that AC prepared by microwave irradiation had higher adsorption capacity on methylene blue and iodin compared with that by muffle furnace． Meanwhile， AC prepared from peanut shell had higher adsorption capacity on methylene blue and iodin compared with that by AC in sales．