Abstract: In order to explore the effect on the operation of coking coal preparation plant produced by the use of the raw coal dry predeshaling process, a study is made with the raw coal washing system of Shihao Mine's coal preparation plant as the object. It is found that the existing heavy medium washing system and flotation system all work with an unstatisfactory performance due to the presence of high-ash fine slime produced in the direct wet cleaning process. Based on the analysis of the adverse effect, the effect of coking coal predeshaling process using compound dry cleaning machine is investigated. As revealed by test result, when the predeshaled >3 mm raw coal is mixed with the <3 mm raw coal, the ash of the 50~1 mm raw coal is reduced from 63.76% to 46.08%, enabling the feed to heavy medium washing system to be dramatically decreased in ash; the feed to flotation system is improved in quality as the yield and ash of the <0.25 mm size in feed drop respectively from 22.77% to 21.58% and from 40.06% to 37.53%; and while ensuring that the total clean coal product has an ash value of 10.38%, the yield of clean coal can see a rise from 34.88% to 37.76%. It proves that the use of the proposed deshaling process is technically feasible.