SNi-30.5Al-39V (at%) alloy is prepared by vacuum non-consumable arc meltingSin this paper.The phase composition and morphology of the alloy at different solidification positions were analyzed by optical microscopy (OM), X-ray diffraction (XRD) and scanning electron microscopy (SEM).And the results show that the solidification structure of Ni-30.5Al-39V(at%) is composed of NiAl+V sheet eutectic.Through the test of fracture toughness and high temperature compression, the results show that the fracture toughness of NiAl-39V alloy is three times that of NiAl alloy, and crack deflection and crack bonding are the main toughening mechanisms.Finally, based on the Arrhenius model, the constitutive relation of NiAl-39V alloy was constructed as ε = 5.398×[sinh(0.037128σ)]_2.3exp(-109.95×10₃/RT) and the activation energy was 109.95 kJ?mol_-1. Keywords: Eutectics; Room temperature fracture toughness; High temperature strength; Constitutive equation