Abstract: In order to make clear how non-metallic inclusions were removed from molten steel through bubble adhesion,water modeling was carried out to monitor the process with high-speed video and image processing software. The mechanism of inclusion removal by bubble adhering was analyzed,and the influencing factors including bubble diameter,inclusion diameter,and inclusion contact angle were also investigated. The results show that it is an effective way to remove inclusions with bubble adhering. The adhering process can be divided into 3 sub-processes:first,the bubbles get close to the inclusion particles; second,the bubbles collide with the particles and attach to them; finally,the particles float up with the bubbles in dynamic stability. When the bottom blowing flow rate is constant,it is effective to decrease the bubble size to improve the efficiency of remove inclusions by adhering to bubbles.