In this paper, high-entropy alloy (HEA) particle-reinforced magnesium matrix composites were successfully prepared by the spark plasma sintering (SPS) technology. The effect of the addition of HEA particles on the microstructural evolution, compressive properties and wear properties was investigated. Given its weak binding with other HEA elements, Cu was the element that separated in the initial HEA-reinforced material and combined with Mg to produce CuMg 2 dispersed in the matrix. The microhardness of the SPSed composite was 45.9% higher than that of the magnesium matrix. The SPSed composite with HEA particle content of 15 vol.% had the best compressive strength, and the ultimate compressive strength reached 269 MPa. With increased AlCoCuFeNi particles, the matrix could avoid fatigue wear, and the abrasive wear mechanism dominated.