As the primary progress of mine filling technology, tailings thickening can significantly improve the tailings dewatering efficiency and tailings utilization rate, which is an important part of tailings safety disposal and mine green development. Firstly, this paper summarized the development process of tailings thickening and dewatering technology, divided the development stage of thickener into ordinary thickener stage, high-efficiency thickener stage and paste thickener stage, and expounded the application of thickener in tailings dewatering process. Then the single flocculation theory and multiple flocculation theory, bed compression theory under static and dynamic compression and gravity thickening theory were introduced, and the latest research progress of each theory was described. In addition, the main research methods of tailings thickening, including static settlement experiment, small-scale thickening experiment and semi industrial thickening experiment, were described. The advanced observation methods such as focused beam reflection measurement technology (FBRM) and particle shape measurement technology (PVM), were introduced. Finally, it puts forward the development direction of tailing thickening technology in terms of personalization, automation and intelligence.