In this study, Al0.5CoCrFeNi high-entropy alloy particles (HEAp) were added to aluminum alloy 2024 to prepare aluminum alloy matrix composites. The composites were prepared via melting, casting, and subsequent rolling (hot rolling, cold rolling, or cryorolling). The results reveal that the adding of HEAp can significantly refine the grains during casting. The cryorolled AA2024 matrix composite with 1 weight percent HEAp content had a tensile strength of 543 MPa and 10% elongation. The Al-Cu crystalline phase of the aluminum matrix composites was more finely dispersed after the addition of an appropriate HEAp content and cryorolling, which led to an increase in both strength and ductility.