Abstract: Based upon an analysis of the motion law of giant magnetostrictive material magnetic domain under magnetic field, a hysteresis model of magnetization-based for a giant magnetostrictive actuator is established. The model incorporates operating conditions of the actuator and fully considers nonlinear and hysteresis characteristics of the material. It includes two sub-models: magnetostriction and magnetization. The relationship between the strain λ and the magnetization M is illustrated in the magnetostriction model. The magnetization model describes the relationships amongst the effective field Heff, the anhysteretic magnetization Man, the reversible magnetization Mrev, the irreversible magnetization Mirr and the total magnetization M, The model is proved to be able to describe the relation accurately between the input current I and the output strain λ by analyzing the experimental result.