The residue from the extraction of agar-agar from Gracilaria debilis was evaluated as a biosorbent for the removal of linear alkyl benzene sulphonate from aqueous solution. The adsorption was studied in batch systems at 25 degrees C and at different pH values. A preliminary screening showed that the average size of the sorbent did not affect the adsorption characteristics. The isotherm equilibrium data were found to fit the Freundlich equation and the Freundlich constant 'K', which is a measure of the capacity of the sorbent, was found to decrease as the pH increased. Initial adsorption rates showed that, as the pH was increased, the initial adsorption rate decreased.