The biomass of a marine alga, Sargassum baccularia, was immobilized by using polyvinyl alcohol as the polymeric matrix. The reusability of the immobilized biomass was studied by using copper as the model metal ion in five consecutive cycles of adsorption-desorption. Hydrochloric acid at pH 1.0 and ethylenediaminetetraacetic acid (EDTA) solution at 2 mM were used as the desorbing agents. Both desorbents were effective in stripping the adsorbed copper from the immobilized biomass over the five cycles. However, copper uptake in Cycles 2-5 was lower than that in Cycle 1, indicating that the two desorbing agents limited the reuse potential of the immobilized biomass in multiple cycles of adsorption-desorption.