Abstract: Adsorption using plant materials has been found an effective technique for removal of dissolved ions. To evaluate the effect of parts of red mangrove and weight on adsorption of Cr (vi) in aqueous medium, adsorption data of freshly prepared red mangrove leaves, bark and root powders were obtained from batch experiments and analyzed as function of powder weight. The results indicated that the adsorption was dependent on weight of mangrove powder. Adsorption capacity decreased from (2996.00 to 175.05 mg/g), for leaves; (2172.50 to 132.40 mg/g), for bark and (2819.50 to 1750 mg/g), for root as weight of powder used was increased from 0.2 to 4g.