The mechanism of inclusion removal by attachment to rising bubble was analyzed,and the movement behavior of inclusion,the mechanism of bubbles/inclusion interaction,collision probability and adhesion probability were discussed.A mathematical model of inclusion removal from molten steel by attachment to fine bubble was developed.The results of theoretical analysis and mathematical model showed that the optimum bubble diameter for inclusion removal is 1 to 2 mm.A new method that argon is injected into the shroud from ladle to tundish during continuous casting has been proposed to produce fine bubble.It provides theoretical guides for production of super clean steel. The mechanism of inclusion removal by attachment to rising bubble was analyzed, and the movement behavior of inclusion, the mechanism of bubbles / inclusion interaction, collision probability and adhesion probability were discussed. A mathematical model of inclusion removal from molten steel by attachment to fine bubble was developed. The results of theoretical analysis and mathematical model showed that the optimum bubble diameter for inclusion removal is 1 to 2 mm. A new method that argon is injected into the shroud from ladle to tundish during continuous casting has been to produce fine bubble .It provides theoretical guides for production of super clean steel.