In this research, the batch removal of Pb2+ ions from wastewater and aqueous solution with the use o two different modified algae Gracilaria corticata (red algae) and Sargassum glaucescens (brown algae) was examined. The experiment was performed in a batch system and the effect of the pH solution; initial concentration and contact time on biosorption by both biomasses were investigated and compared. When we used S. glaucescens as a biosorbent, the optima conditions of pH, Pb2+ concentration and equilibrium time were at 5, 200 mg/L and 70 min, in the range of 95.6% removal. When G. corticata was used for this process, pH 3, 15 mg/L pb2+ concentration and 50 min contact time, resulted in the maximum removal (86.4%). The equilibrium adsorption data are fitted to the Frundlich and Langmuir isotherm model, by S. glaucescens and G. corticata, respectively. The pb2+ uptake by both biosorbent was best described by the second-order rate model.