Abstract: A thermal simulation testing machine was used to conduct a single pass hot compression deformation test under the condition of deformation temperatures of 850-1000 ℃ and strain rates of 0.01-10 s^-1on the Nb micro alloyed hot-dip galvanized DP590 dual phase steel intermediate billet, the influence of deformation temperature and deformation rate on the flow stress of the steel was investigated, and a constitutive equation model for the flow stress of the steel was established, the hot processing map was drawn, the relationship between power dissipation factor and mechanical response of the steel was also analyzed. The results indicate that the flow stress significantly increases with the increase of deformation rate, and the larger the deformation rate, the faster the stress increases. As the deformation temperature increases, the peak stress of the sample decreases. Due to the effect of trace Nb, the recrystallization of the steel is delayed, and no significant dynamic recrystallization phenomenon occurs under all high temperature deformation conditions. A flow stress constitutive equation based on hyperbolic sine equation was established, and the thermal activation energy of the test steel is Q=310.514k J/mol. The safe processing zone for the tested steel is a deformation temperature of 850-950 ℃, a deformation rate of 0.01-0.05 s^-1, and a deformation temperature of 950-1000 ℃, a deformation rate of 0.01-0.40 s^-1.