Abstract: Gleeble-3800 thermal simulation testing machine was used to perform single-pass compression of M152 steel for steam turbine blades at 950-1150 ℃, strain rate of 0.1-10 s^-1 and deformation of 70%. In order to better simulate the on-site process, multi-pass deformation process simulation with different deformation amounts was carried out to study the high-temperature plastic deformation and dynamic recrystallization behavior of M152 steel. Based on the dynamic material model, three-dimensional power dissipation diagram and three-dimensional instability diagram are constructed. The results show that the true stress-true strain curve of M152 steel has the characteristics of dynamic recrystallization, the peak stress increases with the decrease of deformation temperature or the increase of strain rate, and the critical strain for dynamic recrystallization decreases with the increase of temperature. On the basis of the true stress-strain curve, the constitutive equation of material thermal deformation is established, and its thermal activation energy is 290.445 kJ/mol.The optimum hot working temperature range of M152 steel is 950-1150 ℃and the strain rate is 0.1-10 s^-1. In the process of rapid forging deformation, the method of first large deformation and then small deformation is adopted, which is beneficial to obtain uniform microstructure with appropriate grain size.