Effects of hydrogenation on ambient deformation behaviors of Ti-45Al alloy were studied.The stress-strain curves demonstrate that the plastic deformation of the hydrogenated alloys becomes more remarkable than that of the unhydrogenated alloy. Meanwhile,the compression strength and maximum strain are reduced.Both the hydride and hydrogen atoms in the interstices affect the compression deformation behaviors.The reason of the hydrogen-induced embrittlement is that the hydride is easy to become the nucleus of the cracks.And the variation of plastic deformation process is attributed to hydrogen-promoted emission,multiplication and motion of dislocation. Effects of hydrogenation on ambient deformation behaviors of the stress-strain curves demonstrate that the plastic deformation of the hydrogenated alloys becomes more remarkable than that of the unhydrogenated alloys. Meanwhile, the compression strength and maximum strain are reduced. Both the hydride and hydrogen atoms in the interstices affect the compression deformation behaviors. The reason of the hydrogen-induced embrittlement is that the hydride is easy to become the nucleus of the cracks. And the variation of plastic deformation process is attributed to hydrogen promoted emission, multiplication and motion of dislocation