<p>To efficiently recover iron and alumina from high-iron red mud (HIRM), a low-calcium carbothermal sintering method was proposed, and the mineral evolution, metal recovery and reaction mechanism in the simulating Fe₂O₃–Al₂O₃–Na₂O system and actual HIRM were systematically investigated. The results showed that the addition of Na₂CO₃ prevents the formation of FeAl₂O₄ and forms soluble NaAlO₂ to recover alumina during reduction sintering. The SiO₂ and TiO₂ in the original HIRM are converted to Na₂CaSiO₄ and CaTiO₃, respectively, while the hematite and goethite are reduced to Fe. The increase of sintering temperature and Na₂CO₃ usage facilitates the progressive transformation of Na_2−<i>x</i>Al_2−<i>x</i>Si_<i>x</i>O₄ to NaAlO₂. However, the excessive additions of Na₂CO₃, CaCO₃ and coal lead to the formation of weakly magnetic iron-bearing minerals such as Na_0.68Fe_0.68Si_0.32O₂, CaFe₄O₇ and Fe₃C, which significantly deteriorate the iron recovery efficiency. The reduction kinetics of iron oxides in HIRM are primarily controlled by the diffusion reaction model, and the corresponding activation energy is 115.69&#xa0;kJ·mol⁻¹. Under the identified optimal conditions, 87.08% of alumina and 88.05% of iron can be recovered from the HIRM with an iron concentrate grade of 81.05%.</p>