The magnetic adsorbent, FeO@[Ni(HL)]H[PMoO]·2HO (FeO@), is synthesized by employing the nanoparticles FeO and polyoxometalate hybrid . Zero-field-cooled (ZFC) and field-cooled (FC) curves show that the blocking temperature of FeO@ was at 120 K. Studies of FeO@ removing cationic and anionic dyes from water have been explored. The characterization of FeO@, effects of critical factors such as dosage, the concentration of methylene blue (MB), pH, adsorption kinetics, isotherm, the removal selectivity of substrate and the reusability of FeO@ were assessed. The magnetic adsorbent displayed an outstanding removal activity for the cationic dye at a broad range of pH. The adsorption kinetics and isotherm models revealed that the adsorption process of FeO@ was mainly governed via chemisorption. The maximum capacity of FeO@ adsorbing substance was 41.91 mg g. Furthermore, FeO@ showed its high stability by remaining for seven runs of the adsorption-desorption process with an effective MB removal rate, and could also be developed as a valuable adsorbent for dyes elimination from aqueous system.