Ansoft software was used to simulate the electromagnetic force of the cylindrical thin-walled casts under the action of traveling magnetic field, and the influence of excitation currents on mold-filling capacity of different alloys and surface depression of thin-walled casts were investigated. The results show that the magnetic field remarkably influences the mold-filling capacity of alloys and the casting surface depression simultaneously. The mold-filling capacity and the possibility of the surface depression are increased with the square of the excitation current intensity increasing. Under the same excitation current intensity, the excitation current frequency has the optimal value to the mold-filling capacity; the possibility of the casting surface depression decreases along with its decrease below 1000 Hz.