Abstract: Since the plasma spraying technology came into public production and life, its process parameters and the structure and composition of the original powder have been optimized and innovated continuously. Moreover, considerable progress and improvement have been attained. Meanwhile, Al₂O₃, as a common material for spraying plasma, it is extensively utilized in the industrial filed due to its superior abrasive resistance and erosion resistance. In this paper, firstly, the effects of raw feedstock characteristics and the second phase powder particles on abrasion resistance were analyzed and elaborated, respectively. Secondly, the influences of gradient coatings, multi-layer coatings and post-treatments (sealing treatment, laser remelting, etc.) on porosity and corrosion resistance of the composite coatings were also expounded emphatically. In the terms of toughness of the coatings, the effects of the second phase particles and heat treatment on the toughness of the coating was discussed. Finally, the problems faced by the current research were pointed out, and the prospect of the preparation of Al₂O₃-based composite coatings with good comprehensive properties by plasma spraying technology was put forward.