In order to utilize a large amount of tailings generated in the process of tailing mud after beneficiation，a new technology of replacing bentonite as a pellet binder is developed by using high-plastic tailing mud after beneficiation as the main raw material. The results show that the particle size of the tailing mud after beneficiation is very fine and rich in clay minerals，with a particle fraction less than 0. 038 mm of 98. 79% and a mass fraction of 27. 6% of kaolinite. The modified tailings are prepared by co-reaction of 80% tailing mud after beneficiation and 20% F binders，and the binders with excellent performance could be obtained. The expansion capacity of the modified tailing mud is increased from 1. 9 mL/g to 18 mL/g. The specific surface area of iron ore concentrate has a significant effect on the quality of fresh pellets. Taking a weakly spheroidizing iron concentrate as the research object，under the specific surface area of the iron concentrate of 850 cm² /g and the optimal pelletizing process parameters，adding 1% modified tailing mud for pelletizing，the fresh pellet falling strength can reach 11. 10 times/( 0. 5 m) ，the compressive strength can reach 12. 60 N/P，and the bursting temperature ＞ 500 ℃，which is better than the fresh pellet mass of 3% bentonite under the same conditions. During the roasting process，kaolinite dehydroxylation，siderite and calcite decomposition occur，which affect the strength of the preheated pellets，but the combustion of a small amount of organic matter in the modified tailings can promote the formation of secondary hematite and improve the strength of the pellets. Under the conditions of preheating temperature of 1 050 ℃， preheating time of 16 min，roasting temperature of 1 220 ℃ and roasting time of 12 min，the strength of the preheating ball reaches 466. 1 N/P，and the compressive strength of the roasting ball reaches 2 309 N/P，which can meet the requirements of industrial applications.