By means of the numerical simulation method,the mathematical model of inclusions movement in the mold is established under the condition of austenitic and ferritic stainless steel slab production.According to the simulation results,the main zones for inclusion particles accumulation were found and many factors that affected floating-up probability of inclusion particles were identified.These factors include the inclusion particle size,the casting speed and the slab width,etc.It is believed that the inclusion particle size is the key one among these factors.