The central magnetic field intensity of electromagnetic stirring equipment and the melt pool's electromagnetic force were simulated, and the influence of the rotating magnetic field on melt pool electromagnetic force, the flow field and temperature distribution of the melt pool was analyzed by a finite element method. The results show that the electromagnetic force in melt pool decreases slowly at first when increasing the current frequency, and the power loss increases rapidly at the same time. As the frequency continues to rise, the electromagnetic force increases gradually, and the power loss becomes stable. And the magnetic field strength of the electromagnetic stirrer changes periodically in one exciting current cycle. Under the condition of rotating magnetic field, the temperature and the temperature gradient of the melt pool decrease, and circulation along circumferential direction in the melt pool forms whose velocity distribution is uniform.