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CrFeNi2V0.5Wx (x=0,0.25) alloys based on these parameters of mixing enthalpy (△Hmix),mixing entropy (△Smix),atomic radius difference (δ),valance electron concentration,and electronegativity difference(△x) were designed and prepared.The microstructure and room-temperature mechanical behavior of both alloys were investigated.Compressive test results showed that the CrFeNi2V0.5W0.25 alloy had higher yield strength than that of the W-free CrFeNi2V0.5 alloy,although they all exhibited quite larger compressive plasticity (ε ＞ 70％).Compression fracture surface of CrFeNi2V0.5W0.25 alloy revealed a ductile fracture in the face-centered cubic (FCC) phase and a brittle-like fracture in the σ phase.Moreover,tensile test results indicated that the CrFeNi2V0.5W0.25 alloy exhibited excellent mechanical property with an ultimate tensile strength of 640 MPa and a high tensile elongation of 15.7％.The tensile deformation mode of the FCC phase in the CrFeNi2V0.5W0.25 alloy is dominated by planar glide,relating to dislocation configurations,high-density dislocations,and dislocation wall.Therefore,dislocation slip plays a significant role in tensile deformation of CrFeNi2V0.5W0.25 high-entropy alloy.The higher strength of CrFeNi2V0.5W0.25 alloy is predominantly due to the solid solution strengthening of W element and σ phase precipitation strengthening.Combination of the higher tensile strength and plasticity suggests that the CrFeNi2V0.sW0.25 alloy can be a promising aerospace material.