Thin-slab continuous casting and rolling technology is a process integrating casting and plastic deformation.In this study,targeting actions such as slab deformation and liquid core flows during the process of liquid core reduction on thin-slab continuous casting,suggests the fluid-solid coupling method should be used to research the characteristic and patterns of slab deformation during the liquid core reduction process,as well as research liquid core backflows.A material model of the slab shell was obtained through the high-temperature compression test of the cast steel.The analysis of the fluid-solid coupling simulation for liquid core reduction shows that slab deformation concentrates on the narrow side due to the existence of the liquid core.Meanwhile,the stress and strain increases with the increase of the reduction rate and slab thickness.The changing trends of stress and strain are identical under various conditions.The results demonstrate that using greater reduction at the upper part of the slab,which has a higher temperature and thinner slab,is beneficial to the quality of the slab.Moreover,the liquid core is extruded as the reduction is implemented.The quantity of the extrusion increases with the increase of reduction rate and the thickness of thinner shell,which leads to fluctuation of the mould level,making the operation more difficult. Thin-slab continuous casting and rolling technology is a process integrating casting and plastic deformation. In this study, targeting actions such as slab deformation and liquid core flows during the process of liquid core reduction on thin-slab continuous casting, suggests the fluid-solid coupling method should be used to research the characteristic and patterns of slab deformation during the liquid core reduction process, as well as research liquid core backflows. A material model of the slab shell was obtained through the high-temperature compression test of the cast steel. The analysis of the fluid-solid coupling simulation for liquid core reduction shows that slab deformation concentrates on the narrow side due to the existence of the liquid core. Mianwhile, the stress and strain increases with the increase of the reduction rate and slab thickness. changing trends of stress and strain are identical under various conditions. results demonstrate that using greater reduction at the up per part of the slab, which has a higher temperature and thinner slab, is beneficial to the quality of the slab. Moreover, the liquid core is extruded as the reduction is implemented. the quantity of the extrusion increases with the increase of reduction rate and the thickness of thinner shell, which leads to fluctuation of the mold level, making the operation more difficult.