_{:. The effects of Cr content on the microstructures, phases, tensile properties and impact properties of the Ti-Al-V-Zr alloys with addition of 0.76%~1.52%Cr were investigated for nucleus applications. Microstructural analyses were carried out using scanning microscopy,SX-ray diffractionSand quantitative microprobe analysis。Additions of Cr refined the microstructure of such modified alloys, but the microstructure with the amount of 0.76wt% Cr was markedly smaller in comparison with others.XRD results that the total amount of β phase increased with Cr increased at 1.52wt%. Cr additions improved significantly the strength significantly but not improved the plasticityof the modified alloys. T2 alloy has much higher value of the impact toughness and energy among all the studied the alloys. The experimental results indicate that the fracture in Ti-Al-V-Zr alloysinfluencedby Cr additions considering the influence of the number and the shape of the secondαphase. They have the great potential to become new candidates for nucleus applications.}