Abstract: In this paper, hydrogen behaviour in high dislocation density material during plastic deformation was studied by means of SIMS. Experimental results show that hydrogen release rate increases with the increases of stress in elastic deformation stage ; the hydrogen release rate increase dramatically at the very beginning of plastic deformation, and reaches the maximum in the vicinity of yield point, then it decreases with the further increases of strain. The magnitude of hydrogen diffusivity obtained by using Fick's law is 10~(-13)cm~2/s.