[Display omitted] • Efficient fluidized prereduction technique was proposed for high-iron red mud. • Metallization rate of 68.08% and reduction degree of 78.72% was obtained in final prereduced products. • The reduction path of Iron oxide to metal iron was Fe 2 O 3 -Fe 3 O 4 - FeO- Fe. • The reaction thermodynamics of iron oxide with carbon monoxide was analyzed. In order to simulate the pre-reduction behavior of ore powder by coal gas produced by smelting reduction of coal-based electric furnace, an efficient and clean utilization technique for red mud based on fluidized bed carbon monoxide reduction was developed in the present study. Experimental results indicated that a metallization rate of 68.08 % and reduction degree of 78.72 was obtained under the optimal conditions of reduction temperature of 800 °C, CO concentration of 85 %, and reduction time of 30 min. Pre-reduced materials can be used as raw materials for electric furnace melting reduction. The order in which iron oxides were reduced is only related to temperature, and at 800 °C, iron oxides were reduced in the order of Fe 2 O 3 to Fe 3 O 4 to FeO to Fe. During different stages of prereduction, the surface structure of ore particles changes, which is related to the metallization rate of iron oxides in red mud. [ABSTRACT FROM AUTHOR]