The invention provides a high-performance metal-matrix composite preparation method. The method comprises steps: granular raw materials: Al, Fe, Cr, Co and Ni metal powder are acquired; under argon atmosphere protection, a high-entropy alloy powder body is prepared via a ball mill; a pure copper powder body and the high-entropy alloy powder body are weighed; the two are subjected to ball milling and mixing under the argon atmosphere protection, and composite powder is obtained; the composite powder is put in a cold pressing grinding tool, uniform pressurization is carried out, and after packing, a cold pressing green body is taken; the composite after cold pressing is put in a graphite grinding tool of an atmosphere protection sintering furnace, temperature rises to 800 DEG C, hot pressing is carried out and packing is carried out for one hour after temperature of the furnace is stable, and circulating nitrogen is provided during the whole process; and when the furnace is cooled to the room temperature, the copper-matrix composite is obtained. Compared with the prior art, by adopting the above preparation method, the high-entropy alloy and the metal matrix have good mutual dissolution and diffusion performance, the preparation process is simple, the high-entropy alloy has good hot stability, the composite has high density, the interface is good, and the mechanical performance is excellent.