Abstract: For the purpose of slowing down the LF stove the work pressure by improving the craft of slag washing of converter, slag washing of converter in a systematic theory and the experiment of industry was ex-plained. In the industry experiment, the production craft of the iron melt desulphurization-converter smelting steel tapping slag washing-argon station processing-pouring continuous caster was used. The deoxidizer in the converter tapping process was thrown to carry on slag formation of slag charge, through blowing the argon agitation for the tapping process creation good reaction kinetics condition for the deoxidization, the desulphuri-zation, the oxygen content control in 2×10^-5. The process desulfurization percentage was achieved 45%~65%. Moreover, because this craft process time was short, it was lower that compared phosphorus kick-back quantity with the ordinary LF craft. As a result the slag heat preservation function, the middle package temperature was dropped suitable degree to achieve with the LF temperature.