The efficiency of low cost activated carbon prepared from Albizia lebbeck stem carbon[ALSC] for the adsorption of acid yellow 7[Y7] from aqueous solution has been studied as a function of agitation time, dosage of adsorbent, initial dye concentration, temperature and pH of adsorbate solution. The optimal conditions for the adsorption have been arrived and experiments were conducted to find out the Langmuir constants, Freundlich parameters and thermodynamic parameters such as ΔG°, ΔH° and ΔS°. Desorption studies were also carried out.