The ladle slag modifier is mainly produced from calcium oxide and aluminum oxide. This product can be used to improve the purity and yield of molten steel, prevent secondary oxidation of molten steel; enhance desulfurization efficiency during molten steel refining, absorb aluminum oxide inclusions in steel; reduce clogging of tundish nozzles, improve the accuracy of molten steel chemical composition control; and increase the predictability and reproducibility of alloy yield.