The com azo dyes were adsorbed from their aq. solns. (20-100 mu mol/L) on 3 types of sawdust (pine, oak and cherry wood) at 25 degrees C under shaking to study the adsorption kinetics and equil. The kinetics was fitted well to the pseudo-second order model. The expt. isotherms were well described by the Langmuir equation. The effects of pH and ionic strength (0.1 mol/L NaCl) of soln. were studied. The adsorption of the dyes decreased with an increase of pH (2.5-11) and increased with the increase of the soln. ionic strength.