TiAl alloys, novel lightweight, high-temperature metal structural materials, feature low density, high specific strength, and excellent high-temperature performance. However, its narrow hot working window and poor deformation at high temperatures make the formation of alloy components difficult. Adding β-stabilizing elements enhances hot deformation by introducing a disordered β-phase, but the mechanism is unclear. Therefore, Ti-43Al-0.5Re-xCr (x=1, 1.5, 2, at.%) alloys were used as the research objects, and thermal mechanical compression experiments were conducted at 1 150, 1 200 and 1 250 ℃. Flow curves under different conditions were analysed, the effects of temperature and Cr content on the thermal deformation microstructure and dynamic recrystallization were studied, and the microstructural evolution of the Ti-43Al-0.5Re-1.5Cr alloy at 1 200 ℃/0.01 s-1 was clarified. The results indicate that the overall flow stress of the alloy decreases with increasing deformation temperature and Cr content. When the alloys are deformed at 1 150 ℃, many residual lamellar colonies exist in the microstructure that primarily fragment through bending, twisting, and breaking, leading to high deformation resistance. When the alloys are deformed at 1 200 or 1 250 ℃, most of the alloy microstructure is the α phase, which undergoes continuous dynamic recrystallization, resulting in low deformation resistance. Under deformation conditions of 1 200 ℃, a 0.01 s-1 strain rate, and 40% deformation, the degree of recrystallization in the alloy increases with increasing β phase content. Thus, an increase in the Cr content enhances the content of the β phase in the alloy, which promotes the dynamic recrystallization process of the alloy. In the deformed microstructure of the Ti-43Al 0.5Re-1.5Cr alloy at 1 200 ℃, a strain rate of 0.01 s-1, and 40% deformation, many low angle grain boundaries (LAGBs, 2° ~15° misorientation) are distributed around the fine β phases, which interconnect to form numerous small-sized subgrains, resulting in the formation of fine recrystallized grains. Thus, the β phase plays a role in refining the recrystallized grains. The microstructures of the Ti-43Al-0.5Re-1.5Cr alloy samples subjected to different strains were studied, revealing their microstructure evolution at 1 200 ℃/0.01 s-1 hot deformation.