Corrosion and wear are the main factors affecting the service life of key mechanical parts. Therefore, it is of great significance to study new wear-resistant and corrosion-resistant materials. As emerging materials, high entropy alloy (HEA) and medium entropy alloy (MEA) have special microstructure and excellent properties, which have become research hotspots of wear and corrosion resistant materials. In this paper, (AlCoCrFeNi)_{80wt. %}/(CoCrNi)_{20wt. %} composites with excellent wear and corrosion resistance were prepared by SLM technology. And it was annealed. The effects of different annealing temperatures (600 °C, 800 °C, 1000 °C) on the microstructure, hardness, wear resistance and corrosion resistance of (AlCoCrFeNi)_{80wt. %}/(CoCrNi)_{20wt. %} were studied by means of X-ray diffraction, scanning electron microscopy, energy spectrum analysis, electron backscatter diffraction, hardness tester, friction and wear tester, electrochemical workstation and X-ray photoelectron spectroscopy. After annealing at 600 °C, the phase composition of the composites does not change, which is composed of BCC phase and B2 phase, and the grains are more uniform and fine than before annealing. After annealing at 800 °C and 1000 °C, the FCC phase appears and the grains are coarser. The higher the annealing temperature, the heavier the FCC and the larger the grain size. With the increase of annealing temperature, the hardness and wear resistance of the composites increase first and then decrease. Due to the fine grain strengthening effect, the hardness and wear resistance of the sample annealed at 600 °C were the highest. Compared with the sample before annealing, the hardness increased by 26.9 % and the wear weight loss decreased by 32 %. Annealing treatment promoted the enrichment of Cr₂O₃ in the passive film and improved the corrosion resistance of the composites.