Introduced the equipment of dephosphorization station in the steelmaking area of Stainless Steel Branch of Ji-usteel,and probes into the pre-desulfurization process of dephosphorization station.The research results show that the pre-desulfurization process of dephosphorization station can ensure the requirement of providing qualified low-sulfur iron water to AOD,and the desulfurization effect is stable in practice,and the desulfurization rate is more than 80%,the sulfur content of molten iron after pre-desulfurization can reach less than 0.010%,the pre-desulphurization process of dephosphorization station is safe and reliable with no spatter and strong dynamic conditions.