Abstract: The room temperature behavior of the hydrogenated Ti-6Al-4V alloy was investigated by compression test ences of hydrogen on the microstructure and the morphology of fracture were analyzed. The correlation between room-temperature plasticity of the hydrogenated Ti-6Al-4V alloy was explored. The results show that the hardening effect of the hy-drogenated Ti-6Al-4V alloy is enhanced due to the solution strengthening function of hydrogen, but the addition of appropriate hydrogen to the Ti-6Al-4V alloy can dramatically decrease the yield strength and elastic modulus and can increase the compression ratio of the alloy with the α + β binary microstructure. The compression ratio wiU fall largely when there are coarse β grains in the alloy. Moreover, the addition of hydrogen can promote the generation of orthorhombic martensite α″. The fracture of the hydrogenated Ti-6Al-4V alloy generally displays as compounded one of ductile or brittle intercrystalline fracture and transcrystalline fracture.