An adsorption study was carried out for a water system consisted of two components of DBS-Eriochrome Black T on a fixed bed packed with granular activated carbon. The results were tested by data-fitting with breakthrough curves to elucidate which is the most optimum model among three different models-liquid phase controlling model, solid phase controlling model and combined liquid-solid phase controlling model-which were developed by Hsieh and co-workers. Also this work was studied on the breakthrough curve which was affected by variation of bed height, inflow rate of liquid phase, and concentration of each species of inflow liquid phase. It was confirmed that the optimum fixed bed model for the system is the solid phase controlling model. Appearance time of each species at top column is delayed and the width of overshoot is wider with increased length of bed height. Appearance time of each species at the top column is faster and the rate of concentration change of out flow systems is slower with the increase of flow rate. The width and height of overshoot is narrower and shorter, respectively, with the increase of flow rate.