Abstract: The calculation models of electromagnetic field in semisolid slurry preparation by annular electromagnetic stirring (A-EMS) were established, and the effects of stirring current, stirring frequency, crucible materials, cooler materials and gap width on the magnetic flux density in the slurry-making system were analyzed by ANSYS software with corresponding experimental verification. It is concluded that the simulation results are in good agreement with those obtained by experiment, verifying the reliability of the calculation models and the software algorithm. The electromagnetic force mainly distributed in the strring gap enhances the strring intensity of the A-EMS system. At the same gap width, the magnetic flux density increases with an increase in stirring current, but decreases with the stirring frequency increasing. The maximum magnetic flux density can be obtained by choosing both a stainless crucible and a graphite cooler. At the same current and frequency, the magnetic flux density increases as the stirring gap width decreases gradually. In comparison with conventional electromagnetic stirring, A-EMS can produce a finer and more uniform semi-solid structure with the average grain size decreased by 31% under the same stirring power.