Abstract: The effects of nitrogen blowing time,nitrogen flow rate and liquid steel temperature under normal atmospheric condition on nitrogen content were tested and studied during AISI410 stainless steel refining with the 40 t LF and the control model of nitrogen alloying during LF refining was established.The experimental results show that with increase in nitrogen blowing time and nitrogen flow rate,the nitrogen content in liquid steel increased;the nitrogen content in liquid steel was more than 0.05% in the case of nitrogen blowing for 10 min under normal atmosphere;with increase in nitrogen flow rate,the time for saturation of nitrogen in liquid steel was shortened and with decrease in liquid steel temperature,the solubility of nitrogen increased.The analysis on nitrogen solubility was carried out by thermodynamic model and the nitrogen content so calculated agrees quite well with the measured one,which provides reference for controlling nitrogen content by blowing nitrogen gas during stainless steel refining with LF.