Abstract: Deformation behavior of QD08 low carbon steel at high temperature was investigated by thermal simulator with strain rates of 0.1-10 s^-1 at 1 000-1 200℃. The true stress-true strain curves of the low carbon steel at high temperature were obtained, the dynamic recrystallization behavior of QD08 low carbon steel was analyzed, and the constitutive equation of hot deformation was established based on the Arrhenius function with hyperbolic sine form. The results show that the peak stress increased with the decrease of deformation temperature or the increase of strain rate during deformation at high temperature. The predicted value of the peak stress calculated by the constitutive equation was in good agreement with the experimental results. The established constitutive equation could represent high temperature deformation behavior of QD08 low carbon steel.