Abstract: The magnetic nano-barium ferrite/CoNi coatings were prepared by composite electrocodeposition.The influences of barium ferrite nanoparticles on both surface morphology and magnetic properties of the coating were investigated.The effects of electrodeposition parameters,such as barium ferrite particles concentration,current density,bath temperature and plating time,on the coercivity and maximal energy density of nanocomposite coatings were also discussed.The results show that nanocomposite coatings with excellent magnetic properties could be obtained with the optimization of composite electrodeposition parameters after the addition of barium ferrite nanoparticles.And its maximal energy density and coercivity were improved obviously.The above four kinds of parameters had significant effects on the maximal energy density and coercivity,which influence laws were different from each other.