A new three-dimensional mathematical model describing the electromagnetic stirring in the laser remelting is developed. The method combining the finite element and finite volume is used to deal with coupling electromagnetic field with flow field and temperature field. The influence of electromagnetic field on temperature field and flow field are analyzed. The results show that the electromagnetic force is distributed circumferentially at horizontal plane, the magnitude of the tangential force decreases from edge to center; Under the effect of rotating magnetic field, the temperature and temperature gradient in the molten pool are slightly reduced; Liquid in the molten pool tends to rotary motion, it is similar that the distribution of velocity field and electromagnetic force; The circulation in the longitudinal of molten pool increases, which is benefit for heat transfer of molten pool and accelerates cooling speed; The distributions of electromagnetic field and flow field are affected by the intensity of exciting current. It provides the theoretical reference for laser processing.