The vortex formation in draining the melt in ladle can be suppressed by the reduction of the tangential flow velocity of the melt. Two magnetic devices were designed in order to reduce the tangential flow velocity and tested with wood metal melt. One consists of 4 permanent magnets (PM device) and the other consists of an electromagnet (EM device). Magnetic flux density around each device was calculated and compared with the measured one. Induced body force in the melt was calculated with both of the calculated magnetic flux density and velocity profile. The dimensionless vortex formation height, where the vortex formation height is divided by orifice inner diameter, decreased from 1.7 down to 0.85 in both cases of the PM device and the EM device as the static magnetic field increased up to 0.17 T.