To purify the molten steel, the effect of flow rate of soft blowing on inclusions removal during LF refining and the effect of Ca-treatment on inclusions were studied. Samples were taken from LF refining processes and continuous casting mold of the 90tBOF-90tLF-150 X 150 mm2CC manufacturing process in Shanxi Antai Group Company. Thereafter, the samples were analyzed by optical microscope (OM) and scanning electron microscope (SEM) with energy dispersive spectrometer (EDS). The result shows that the inclusions larger than 10 μm were removed efficiently when the flow rate of soft blowing is between 250-300 L/min. Specifically, the average size of inclusions was decreased from 2.34 to 1.18 μm and area fraction from 3 467.7 to 413 μm2/mm2 after soft blowing. In addition, from the analysis of area fraction of inclusions, the performance of inclusions removal was found not efficient when the flow rate of soft blowing was higher than 340 L/min. The morphology of inclusions before and after Ca-treatment was analyzed. The result shows that the deoxidation products Al2O3 a and MgO·Al2O3 spinel inclusions were modified as low melting point calcium aluminate inclusions. Besides, some of inclusions were modified as spherical complex inclusions with Al2O3 core and CaS layer.