Abstract: By optimizing the nozzle parameters of oxygen lance, the oxygen supply intensity of 120 t converter is increased from 3.6 m³/(min•t) to 4.5 m³/(min•t) , and the oxygen lance blowing system and charging system of converter are optimized to ensure the end liquid composition satisfying the requirement of production. The production practice shows that the end-point composition of converter by using the new oxygen lance nozzle is similar to the original process, the oxygen blowing time of converter can be shortened from 15. 1 min to 12. 8 min, the tap-to-tap time can be shortened by 2. 4 min, the total iron content in slag can be reduced from 18.5% to 17.5%, and the annual output can be increased by 120 000 tons.