A core-shell composite of chitosan on Fe3O4 nanoparticles was successfully synthesized and pepsin enzyme was immobilized on it via imine linkages. The supported aspartic protease was characterized by IR spectroscopy and its morphology was studied by X-ray diffraction (XRD) analysis, as well as scanning electron microscopy (SEM) and transmission electron microscopy (TEM), confirming its spheroidal structure. Thermal analysis was carried out by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) ...