In order to investigate the influence law of different conditions on the strength of the rotary hearth furnace metallized pellets, further optimize the production parameters of the rotary hearth furnace, and clarify the direction of metallized pellets resource utilization, the chemical composition and particle size composition of typical metallurgical sludge are analyzed, the effects of different raw material ratios, drying and roasting systems, cooling and forming methods on the compressive strength of metallized pellets in the direct reduction process of rotary hearth furnace are studied, and the feasibility utilization of rotary hearth furnace of metallized pellets into blast furnace is discussed. The results show that the ratio of raw materials is one of the main factors affecting the compressive strength of metallized pellets. When the ratio of blast furnace cyclone ash is 56% , the metallized pellets have empty shell pulverization phenomenon, when the ratio of blast furnace cyclone ash, steelmaking primary ash, secondary ash, blast furnace bag ash and blast furnace pre-furnace ash is 18% , 20% , 10% , 26% and 26% respectively, the compressive strength of the metallized pellets can reach 2815 N/P. Under the same ingredient conditions, the strength of metallized pellets after roasting in the freeze process is significantly better than that of the pelletizing process, and the tumbler strength of metallized pellets is comparable to that of sinter.