The article uses Fulent software to simulate the design of supersonic oxygen lance and sec-ondary combustion oxygen lance based on 120 t converter(5-hole staggered type and 8-hole homo-geneous type),to compare and analyze the characteristics of jet velocity distribution of the three types of lances and their influence on the stirring ability of the molten pool after mixing 10%CO2.The simu-lation results show that:at L<1.05 m,the main oxygen jet velocity of the 5-hole staggered oxygen lance is the largest due to the larger flow rate of the single hole of the sub-hole;at L>0.57 m,the velocity of the 8-hole homogeneous oxygen lance is less than that of the supersonic oxygen lance;at 1.05 m<L<1.8 m,the main oxygen jet velocity of the 5-hole staggered oxygen lance is the smal-lest.The stirring intensity of the three types of oxygen guns was found to be the best position at 1.45 m.Under this position,the size of the impact area was ranked as 8-hole uniformly distributed oxygen lance>supersonic oxygen lance>5-hole staggered oxygen lance,and the size of the impact depth was ranked as 8-hole uniformly distributed oxygen lance>5-hole staggered oxygen lance>super-sonic oxygen lance,and the 8-hole uniformly distributed oxygen lance had the largest impact depth and area,which had the strongest impact ability to the molten pool accordingly.