Abstract: For tackling the problem relating to the relatively high ash of the cleaned coarse slime, the paper starts with an introduction to the coarse slime recovery system and then goes to make an analysis of the factors causing the high ash of the cleaned coarse slime, proceeding from the treating process and equipment aspects. Through adoption of a series of measures, such as improvement of equipment management and perfection of separation processes, there is no need for the heavy medium separation system to produce a clean coal product with an unnecessarily low ash because of the reduction of the content of ＜ 0.25 mm high-ash fine coal and the significant drop of the ash of coarse slime. This is much beneficial, therefore, to the improvement of economic performance of the plant.