Abstract: Based on the principle of giant magnetostrictive materials (GMM), the internal magnetic field of actuator was designed. In order to explore the rationality of magnetic field design and the relationship between magnetic induction intensity and excitation current of giant magnetostrictive actuator, the internal magnetic field of giant magnetostrictive actuator was simulated by ANSYS finite element analysis software. The results showed that the magnetic field design of the giant magnetostrictive actuator was reasonable, and the magnetic induction intensity in the giant magnetostrictive material increased with the increase of the current, and the magnetic induction intensity of the giant magnetostrictive material tended to saturation gradually.