Activated carbons are known for their high adsorption capacities. In this study, an activated carbon with high adsorptive capacity was prepared from Euphorbia antiquorum L wood. Impregnation with H3PO4 solution followed by activation at 800° C results an activated carbon with a surface area of 918 m2/g and more developed porosity. The prepared adsorbent was used for the adsorptive removal of four categories of dyes. Various kinetic models were applied for the analysis of the adsorption process and pseudo second order model fits well for the adsorption system. Based on the results of kinetic models, Intra particle diffusion model and energy of adsorption, a four stage pore diffusion mechanism was illustrated.