In this work, the mechanical properties and solid particle erosion wear behavior of LaMgAl11O19-Al2O3 ceramics toughened and reinforced with LaMgAl11O19 platelets were investigated. The effects of LaMgAl11O19 additions, impingement angles ( 30 degrees, 45 degrees, 60 degrees, 75 degrees, and 90 degrees), and erosion temperatures varying from room temperature to 1400 degrees C on the erosion rates and material removal mechanisms of LaMgAl11O19-Al2O3 composites were systematically studied. The results indicated that LaMgAl11O19-Al2O3 ceramics exhibited superior erosive wear resistance compared to monolithic Al2O3 ceramics at room and elevated temperatures due to their enhanced mechanical properties and improved microstructure resulting from the introduction of an appropriate amount of LaMgAl11O19 platelets. Examination of the eroded surfaces of LaMgAl11O19-Al2O3 composites revealed that erosion temperatures and impingement angles play important roles in determining the erosion behavior and mechanisms of the tested materials. For the case of elevated temperature and oblique erosion, plowing and subsurface intergranular fracture are the predominant mechanisms resulting in material removal, whereas at room temperature and normal impact, the erosion process of the targets is primarily dominated by grain ejection and lateral crack intersection.