The steelmaking slag has not yet been utilized effectively in our country.The practice is limited due to the high phosphorus content in slag.This work proposed the steelmaking slag reacts with C-saturated iron bath in a slag regenerator.This method can remove phosphorus from slag by carbon reduction;meanwhile,can also recover the Fe and Mn in slag.The reduction slag can recycled in a waste-free steelmaking process.Through thermodynamic analysis and research conclusion,this method is identified to be feasible.