<p>This research seeks to improve high-temperature wear performance of magnesium-based alloys by examining the tribological behavior of in situ Aluminum Oxide (Al₂O₂) reinforced Magnesium–Lanthanum (Mg-La) composites. This research addresses the deficiencies of conventional magnesium alloys which exhibit low abrasion resistance when under thermal stress, although they possess an exemplary strength-to-weight ratio, to develop a lightweight, high strength material system for aviation uses. Al₂O₂-reinforced Mg-La composite is produced and compared to the unreinforced Mg-La alloys AZ91, ZE41, and Mg-6Gd-Zr-Ag. All alloys undergo wear testing at different loads and temperatures. Subsurface microstructural evaluation is conducted to clarify thermal stability, work hardening behavior, and grain recrystallization. Wear mechanism maps are created statistically to illustrate operational parameter impact on deformation and wear mechanism. AZ91 exhibited the highest wear resistance (0.25&#xa0;mm³/Nm), followed by ZE41 (0.22&#xa0;mm³/Nm), Mg-6Gd-Zr-Ag (0.17&#xa0;mm³/Nm), and the Al₂O₂-reinforced Mg-La composite (0.12&#xa0;mm³/Nm). Although wear resistance is lower than that of traditional alloys, the reinforced composite benefits from exceptional thermal stability, improved work hardening, and a higher resistance to grain recrystallization. The wear mechanism maps also illustrate how load and temperature significantly affect the deformation and wear processes, highlighting the advantages of the in situ Al₂O₂-reinforced Mg-La composite. In situ Al₂O₂-reinforced Mg-La composite effectively improves the high-temperature wear performance of Mg-based alloys, offering a promising approach for designing lightweight, thermally stable materials suitable for extreme service environments, particularly in the aerospace sector.</p>