The production flowsheet of test stainless steel 20Crl3 (/% : 0.20C
0.37Si
0.54Mn
0.030P
0.002S
12.22Cr
0.007Al) is 25 t EAF-VOD-LF-ingot casting. The effect of [Si
]
and slag basicity on (Cr
2
O
3
) content in slag and the desulphurization efficiency of slag by silicon deoxidation process have been analyzed. The calcium yield for stainless steel 20Cr13 by VOD-LF with Si deoxidation refining process is 99. 27%
the [ S
]
at LF refining beginning is 0. 014% and at end refining [ S
]
is 0. 007% to meet the requirement of actual production and save the consumption of aluminium ingot and high-carbon ferrochrome and decrease the production cost of stainless steel 20Crl3.