Abstract: Smoothed finite element method is based on strain-smoothed technology, it avoids using the isoparametric transformations during numerical integration, and has certain advantages in simulating large deformation problems of soft materials. A numerical format for simulating large deformation of hard magnetic soft materials based on strain-smoothed technology has been established, and the necessary stress tensors and constitutive tensors have been provided. The bending characteristics of hard magnetic soft material beams with different aspect ratios under external magnetic field were studied, and the magnetic load displacement curves obtained were compared with experimental results, evolution process of the morphological of hard magnetic soft material structures with different directions of residual magnetic field under the action of an external magnetic field was simulated, and the calculated final deformation morphology was compared with experimental results. The numerical results indicate that the results obtained by using this numerical format are in good agreement with the experimental results. There is significant deformation at the sudden change in the direction of the residual magnetic field inside hard magnetic soft materials. The research results can provide reference for the mechanical analysis and deformation control design of soft robots and intelligent flexible structures composed of hard magnetic soft materials.