The sorption of Basic Blue 69 and Acid Blue 25 onto wood has been studied in terms of pseudo-second order, intraparticle diffusion and pseudo-first order chemical sorption processes. The batch sorption model, based on the assumption of a pseudo-second order mechanism, has been developed to predict the rate constant of sorption, the equilibrium capacity and initial sorption rate with the effect of initial dye concentration, wood particle size and temperature. An equilibrium capacity of sorption has been evaluated with the pseudo-second order rate equation as well as by the Langmuir isotherm and operating Line method. In addition, an activation energy of sorption has also been determined based on the pseudo-second order rate constants.