Abstract:High entropy boride ceramics have broad application prospects in aerospace, automotive engine and nuclear reactor fields. In order to improve the performance of high entropy boride ceramics and expand the family of high entropy boride ceramics, (Hf0.25Zr0.25W0.25Ti0.25)B2 high entropy boride ceramic was prepared by boron/carbothermal reduction combined with SPS(Spark Plasma Sintering) in this paper. The phase composition, microstructure and mechanical properties of the powder and ceramic were studied. The results show that after heat treatment at 1600℃,not only the high entropy phase but also W2B5 phase can be detected in (Hf0.25Zr0.25W0.25Ti0.25)B2 high entropy boride powder(particle size(0.29+0.03)μm).After sintering at 2000℃,the second phase W2B5 decreases, and the diffraction peaks of the high entropy phase shift to a higher angle. The density of ceramic reaches 95.7%.After the introduction of WB2, the high entropy boride ceramics exhibit excellent mechanical properties. The hardness is (21.3+1.5)GPa and fracture toughness is (3.00+0.22)MPa·ml/2.