The objective behind this study is to investigate the phenomenon and kinetics of Cd(II) ion biosorption by the algae fibers, as well as the development of mathematical model that would describe the phenomenon of ions transport through porous algae. The results obtained have shown an inter-particle rate constant of diffusion K-int = 0.188 (mgg(-1)min(-1/2)), R-2 = 0.999, and adsorption amount at equilibrium Q(Seq) = 1.87 mgg(-1). These results indicated that the diffusion of ions existed in the porous algae. The proposed mathematical model is used to optimize the biosorption of heavy metal ions by connecting the model parameters with the fiber performances.