Abstract: The thermal deformation and heat treatment experiments of GH4080A superalloy were performed, and the microstructure of the alloy after thermal deformation and heat treatment were observed by optical microscope and scanning electron microscoe to study the influence law of thermal deformation parameters and heat treatment parameters on the microstructrue evolution of GH4080A superalloy. The results show that:in the temperature range of 1030-1070 ℃, the heat treatment temperature has little effect on the grain size, and the grain shape at 1070 ℃tends to be more equiaxed grain; with the extension of heat treatment time, it can promote the redistribution of elements inside the alloy, but it does not affect the grain size; the grains in the large deformation zone of GH4080A superalloy grow abnormally after heat treatment, while the grain growth amount in the small deformation area is relatively small. With the increase of strain rate, the dynamic recrystallization of GH4080A superalloy is incomplete and there are original coarse grains, resulting in uneven microstructrue and coarse grains after heat treatment; the influence law of deformation temperature on the microstructrue after heat treatment is complicated, the original coarse grains are not fully recrystallized at lower temperature, and coarse grains remain after heat treatment, and the dynamic recrystallization at higher temperature is fully. However, too high temperature can lead to grain growth after heat treatment.