Abstract: Potassium salt as a strategic non−metallic mineral in China, its safe and efficient exploitation was directly related to national food security and economic and social stability. Aiming at the goaf left by underground mining and the solid−liquid tail waste generated by beneficiation, The characteristics of underground mining methods and filling methods of solid sylvite mines were summarized, besides generally introducing the cementation mechanism of different filling cementitious materials and the current research situation. The research directions covering cementitious material formula and proportion, mechanical properties of tailing−waste−colloid cement, and supporting technology of cementitious filling were clarified, so as to provide references for the potash mine developers to choose suitable mining methods, filling methods and solid−liquid tailing−waste−based filling materials. The analysis shows that the composite cementitious material with low dosage of magnesium chloride−oxygen cement, fly ash and additives is the key to realize the high efficiency and safety of solid potash underground mine which produces low tailing waste emission and low−cost of filling mining at the present stage.