Abstract: The production flowsheet of titanium stabilizing austenite stainless steel 321 (/% : 0. 04 ~0, 08C, 0.40 ~ 0.70Si, 0. 80~1.50Mn, ≤  0.035P, ≤ 0.005S, 17. 0 ~ 18. 0Cr, 9.0~9.5Ni, 0,20~0.40Ti, ≤ 0.0200N) is 90t EAF45 t AOD-LF-180 mm x 1 238 mm slab casting. The "floater" in liquid of steel in mold occurs and the nozzle blocking produces in casting process. Based on analysis on TiN precipitation rule it is obtained that in order to decrease of TiN precipitation in liquid it should be controlled [N] ≤ 0.015 0% , [Ti] ≤0.25% and temperature of liquid in tundish 〜 1 500 °C. With process measures including using extra-pure Ar stirring in whole AOD process, controlling ladle slag thickness 150 mm, [O] 15 x 10^-6 ~20 x 10^-6 and [N] ~ 110 x 10^-6, and using shielding slag with basicity 0. 75 and viscosity 0. 165 pa ·s at 1 300 ℃ , the yield of Ti increases from original 40% to 52% , the N content in finished liquid decreases from 0.014 0% to 0.010 5% , the inner diameter of nozzle at finished casting increases from original 42 mm to 50 mm, and the defect of rolled products decreases from original 3. 5% to 1. 2% .