Recently,nano-technologies have been adapted in the research to eliminate of toxicchemical and biological agonist. Particularly, metal oxide particles are consideredas reactive adsorbents for the decontamination of toxic materials. The important feature is to enhance the surface chemical reactivity toward incomingadsorbates. It is expected that the adsorption efficiency of nano-sized MgO greater than commercially common used MgO. In general, there are three kinds of synthesis method for nano-sized MgO: Polyol, Hydrothermal, and Aerogel method. In this study, nano-sized MgOs were synthesized with three different methods. The synthesized MgOs were characterized by XRD, BET, TGA, and TEM. The adsorptive properties and removal efficiencies of toxic compound (sulfur compounds in CH 4)on MgO were tested by the breakthrough experiments. And the variation of adsorptioncapacity by calcination condition was investigated.