Al₂O₃–C refractories are important for the continuous casting process. It is essential for safe and effective steel making processes to enhance the strength and oxidation resistance of Al₂O₃–C refractories. A compound MAB phase Cr₂AlB₂ has attracted recent attention due to its high fracture toughness, high damage tolerance and excellent oxidation resistance. In this work, a ternary layered compound Cr₂AlB₂ was introduced into the Al₂O₃–C refractories.The structural evolution of Cr₂AlB₂ in Al₂O₃–C refractories after treated at different temperatures and its effect on the comprehensive properties of Al₂O₃–C refractories were analyzed by X-ray diffraction,scanning electron microscopy and transmission electron microscopy. The results show that a gradual decomposition of Cr₂AlB₂ in Al₂O₃–C refractories generates a core–shell structure of CrB and Al₂O₃ covered with Al₂O₃, and catalyses the formation of carbon nanotubes and carbon fibers on the surface of the core–shell structure after thermal treatment at 800–1200 ℃. Cr₃C₂ covered by BN structure is formed inside the core-shell structure after thermal treatment at 1200–1600 ℃. As a result, the densification of Al₂O₃–C refractories is facilitated, and the cold modulus of rupture and oxidation resistance is enhanced. The cold modulus of rupture after coking at 1400–1600 ℃ is increased by approximately 9%, and the oxide index after treated in air at 1400 ℃ is reduced from 44%to 31%.