Alumina/alumina ceramic matrix composites (Al₂O₃/Al₂O₃ CMCs) have demonstrated broad application prospects in aerospace, energy, and other high-temperature fields due to their low cost, short fabrication cycles, and excellent oxidation resistance. This review systematically summarizes the key challenges and recent advances in the preparation of Al₂O₃/Al₂O₃ CMCs, focusing on core technical issues such as low-temperature sintering, homogeneous densification, and microstructure control. A comparative analysis of fabrication techniques, including sol-gel, slurry infiltration, and automated fiber placement, highlights their respective advantages and limitations. Furthermore, practical applications in aircraft engine combustors, exhaust components, aerospace thermal protection systems, high-temperature parts in automotive and low-altitude unmanned aerial vehicle, and industrial kilns are discussed, demonstrating the material’s superior thermal stability and lightweight potential. Future research should prioritize process optimization, strengthen automated production, and expand application scenarios to further advance the development of high-temperature structural materials.