Abstract: In coal preparation plant suing wet method, coal slime water treatment constitutes an important process link involving even the entire coal washing process. The difficulties in treating the water exert an adverse effect on the normal operation of a great majority of coal preparation plants. At the present, the emphasis of study is directed largely toward the slime water treatment process, equipment and reagents while the related theory and mechanism in this aspect still awaits in-depth investigation. Following an elaboration on the advances made in theoretical research both at home and abroad in recent years, as well as the introduction of the fractal theory and DLVO hypothesis is proposed for guiding the slime water clarification process, so as to achieve an improved result and meet the environmental protection and clean coal production requirements.