Abstract The layered material of sodium ferric silicate (SFS) has good adsorption properties for cationic dyes, but its stacking properties limit its application. The organic–inorganic composite assembled by macromolecular polymer and inorganic material can improve this situation. Carboxymethyl chitosan (CC) was loaded onto SFS, and the compound was characterized by X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscope (TEM), Brunauer–Emmett–Teller (BET), zero energy thermonuclear assembly (Zeta), and Fourier transform infrared spectroscopy (FT‐IR). The results showed that CC was successfully supported in the layered structure of SFS, and the adsorption capacity of the composite for methylene blue (MB) was 729.67 mg g −1 . The adsorption process was described by pseudo second‐order kinetics, Langmuir isothermal equation, and intraparticle diffusion. The adsorption process was endothermic and spontaneous, and the monomolecular adsorption was dominant.