The hot extrusion deformation of FGH96 alloy was carried out under different extrusion process parameters, and the influences of extrusion temperature, extrusion ratio and extrusion speed on the grain structure, γ′ phase of hot-extruded FGH96 alloy bar and the influences of γ′ phase on recrystallization grain growth were studied. The results indicate that the dynamic recrystallization in the FGH96 alloy happens within the range of extrusion process parameters selected by the test, and the recrystallized grain size increases with the increasing of extrusion temperature. In the microstructure of FGH96 alloy bar, the large-size γ′ phase is distributed along the grain boundary in a chain shape, and small-size γ′ phase is dispersed and distributed inside the grain. With the increasing of the extrusion temperature, the large-sized γ′ phase at the grain boundary gradually dissolves, the grain boundary remove, the migration resistance decreases, and the recrystallized grains grow up. At the extrusion temperature of 1100 ℃, the large-sized γ′ phase at the grain boundary begins to dissolve rapidly, and the recrystallized grains begin to grow obviously. The influences of extrusion ratio and extrusion speed are mainly reflected in the dual effects of effective strain and deformation latent heat on the nucleation and growth of recrystallization within unit time, and excessively large or small extrusion ratio or extrusion speed cause uneven structure.