Abstract: The hot deformation behavior was investigated at the temperature of 1080~1180℃ and strain rate of 0.01~10 S-1 for GH4720Li alloy, by using the hot compression tests. True stress-true strain curves and deformation microstructures were investigated. Constitutive equation and processing map for hot working were established. The results show that dynamic recrystallization is the dominant softening mechanism during hot deformation. Fully recrystallized grain is obtained at strain of 0.7, temperature of 1120~1180℃ and strain rate of 0.1~1 S-1. The optimum hot deformation temperature is 1120~1140℃. The behavior of γ′ phrase precipitation is the reason for the prominent change of the peak value of stress and the hot deformation activation energy. The hot deformation activation energy value 602KJ/mol is the minimum at the temperature of 1160℃. When the strain rate is greater than 1 S-1, the alloy will occur to the flow instability.