A novel L-arginine modified magnetic bioadsorbent (Fe3O4-CS-L) was fabricated to remove Zn(II), Cd(II) and Pb(II) from aqueous solution by adsorption method. Several techniques such as FT-IR, SEM, XRD, TGA and VSM were used for characterizing the Fe3O4-CS-L. The results showed that the Fe3O4-CS-L was successfully prepared. Batch experiments were conducted to investigate the parameters affecting the adsorption of the novel magnetic bioadsorbent to metal irons, such as adsorption isotherm and adsorption kinetics. The adsorption equilibrium was commendably described by pseudo-second-order model. Langmuir model was better than Freundlich model to describe adsorption isotherm data and the predicted maximum adsorption capacities of Zn(II), Cd(II) and Pb(II) were 256.41 mg/g, 156.99 mg/g and 128.63 mg/g, respectively. Competition adsorption results showed that the adsorption order of Fe3O4-CS-L to metal ions was Pb(II)> Zn(II)> Cd(II). Moreover, regeneration studies suggested that Fe3O4-CS-L has a good recyclability. All the results showed that Fe3O4-CS-L could be a promising material in environment pollution cleanup. (C) 2017 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.