A method for producing multiphase particle-reinforced metal matrix composites is provided. The method is characterized by the combination of an in-situ reaction process under an external electromagnetic field and an in-situ crystallization process under an external electromagnetic field. A traveling wave magnetic field or a rotating magnetic field is employed during the in-situ reaction process, and a rotating magnetic field or a high frequency magnetic field is employed during the in-situ crystallization process. Said method can obtain homogeneous, gradient enhanced or surface reinforced composite materials.