Abstract: The thermal deformation of 5052+Er alloy at high temperature was carried out with the Gleeble-3500 type thermal/force simulation test machine and the effects of deformation temperature and strain rate on the high temperature compression behavior of 5052+Er alloy were studied. The results show that when the strain rate is 0.01 s^-1, the true stress-true strain curve presents typical dynamic recrystallization features; When the strain rates are 0.1 s^-1 and 1 s^-1, the curves are characterized with dynamic recovery; When the strain rate increases to 10 s^-1, after the flow stress reaches the peak value, the zigzag wave appears, and the dynamic recrystallization of the alloy occurrs; With the increasing of the deformation temperature and the decreasing of the strain rate, the rheological stress of the 5052+Er alloy decreases gradually, and the rheological stress equation of the thermal compression deformation of 5052+Er alloy is σ=$95.42\left\{\left(\frac{\dot{\varepsilon} \exp \left(\frac{155500}{R T}\right)}{2.69 \times 10^{18}}\right)\right\}^{0.1877}+\sqrt{\left(\frac{\dot{\varepsilon} \exp \left(\frac{155500}{R T}\right)}{2.69 \times 10^{18}}\right)^{0.3754}+1}$, and the errors between the calculated values of the peak stress and the measured values under different thermal deformation conditions are lower than 10%.