Fundamental investigation on adsorption of Cu2+ and Ni2+ ions on Sargassum sp. was performed in fixed-bed column. The Langmuir isotherm fitted well the biosorption equilibrium and the maximum Cu2+ and Ni2+ uptake capacities were 1.35 and 1.06 mmolg- 1, respectively. Mappings of copper and nickel in the algae surface using energy dispersive X-ray spectroscopy indicated a homogeneous distribution of Cu- and Niadsorbent sites. Fourier-transform infrared analysis revealed that the main chemical groups involved in the copper and nickel biosorption were carboxyl, ether, alcoholic, amino, and sulphonic groups.