Multiferroic composite materials consist of ferroelectric and ferromagnetic phases.The interrelation of ferroelectricity and ferromagneticity allows the magnetic control of ferroelectric properties and the electric control of ferromagnetic properties.Namely,these composite materials can output the magnetoelectric (ME) effect by introducing indirect coupling via mechanical strain between the two phases.They are interesting for use in innovative multifunctional applications such as energy harvesting device.The macroscopic ME property is dominated by microscopic inhomogeneous structure.In this study,a multiscale simulation is proposed for design of multiferroic composite materials.An asymptotic homogenization theory is employed for scale-bridging between macrostructures and microstructures.We can estimate the homogenized physical properties of the macrostructure through upscaling process and evaluate the microscopic mechanical,electric,and magnetic behaviors in response to macrostructural external loads through the downscaling process.The influence of three factors,which are the combination of ferroelectric and ferromagnetic phases,the volume fraction of phase and the microstructure,are numerically investigated through the proposed simulation.CoFe2O4 and Terfenol-D are selected for the ferromagnetic phase and BaTiO3 and PMN-PT are employed for the ferroelectric phase.The relation between macroscopic physical property and the inhomogeneous microstructure is discussed for enhancement of ME property.