Abstract: The force condition of spherical inclusion particles in 1873 K liquid steel was investigated by theoretical analysis and numeric simulation. It is found that the pressure gradient Force, virtual mass force, Saffman force and Magnus force are little and can be ignored in static steel and turbulent flow fields. With increasing inclusion particle size, the Brown force imposed on the particles with a bigger size gradually decreases in static liquid steel and homogeneous turbulence fields. When the particle size is bigger than 20 μm, the Brown force will have no influence on particle movement and can be ignored. The Brown motion of the particles with the size smaller than 10 μm is very violent, the Basset force and Brown force imposed on the particles per unit mass become the main force determining particle movement. As for the big-size particles (D>50 μm), the Basset force, mass force and Stokes force work together to influence the movement, collision and removal of the particles.