Under the conditions of the deformation temperature of 800-1000 ℃ and the strain rate of 0.1-1 s-1, a hot compression test of SCM920 steel with a compression amount of 60% was conducted by thermal simulation test machine Gleeble-3800 to obtain its high-temperature stress-strain curves. Then, by calculating the coefficient of expansion, it was determined that the friction effect had a significant impact on the flow stress, and the curve was corrected by friction. Furthermore, based on the Arrhenius equation and the Zener-Hollomon equation, a hyperbolic sine constitutive equation suitable for SCM920 steel was constructed, and on this basis, the hot compression process under different deformation conditions was numerically simulated by finite element software Deform-3D to research the influences of deformation temperature and strain rate on stress and strain. The results show that the flow stress of SCM920 steel significantly decreases with the decreasing of strain rate and the increasing of deformation temperature, and the friction effect has a significant impact on the flow stress and gradually increases with the increasing of deformation degree. The overall trend of the stress-strain curve is consistent before and after friction correction. The increase of deformation temperature effectively reduces the flow stress and improves the deformation capacity of metal, and the increase of strain rate increases the maximum principal stress and enhances the stress change gradient of specimen.