The typical aero-engine defects such as damage and attachment defects, the application of additive remanufacturing and subtractive remanufacturing in the field of aero-engine blade remanufacturing and theirs effects are studied in this review. Taking the remanufacturing effect and cost of blades as evaluation indexing, the principles, advantages and disadvantages of additive remanufacturing technologies such as laser cladding and welding, and subtractive remanufacturing technologies such as water-based liquid cleaning and mechanical and physical methods are summarized, and the development trend of aero-engine blade remanufacturing is expounded.