Abstract: Aiming at the steelmaking process of IF steel in Han-Steel, the relationship between key parameters and the defects of the rolled sheet was investigated, and the correlation among the parameters was also analyzed through the logic regression analysis, correlation statistics, descriptive statistics and other methods in the statistical software SPSS. The results show that the probability of inclusion defects in the rolled sheet reduces in the steelmaking process of IF steel when the end-point temperature of BOF is controlled in the range of 1695-1700℃, the oxygen blow amount below 250 m³, the holding time in the range of 30-40 min and the oxygen content before adding aluminum below 3. 9×10^-4. Besides, the improvement measures were carried out and the results show that the optimization measures can reduce the inclusion defects of rolled IF steel sheet.