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The Ti{sub 3}Al-based titanium aluminides, which exhibit high specific strength, excellent creep resistance and good oxidation resistance at elevated temperature, are promising materials for high temperature application in the aerospace industry. The room temperature brittleness of Ti{sub 3}Al alloys could be improved by the addition of various {beta}-stabilizing elements (Nb, V, and Mo) to the alloy and by thermo-mechanical treatments. After the thermo-mechanical process, the Ti{sub 3}Al-based alloys usually have duplex ({alpha}{sub 2} + {beta}) phases and exhibit a microstructure of texture. Recently there are a number of papers reported the superplastic behavior of Ti{sub 3}Al-based alloys. Besides the fine grain size, the addition of Nb element and the structure of texture could also improve the superplasticity of Ti{sub 3}-Al-Nb alloys. It was concluded that the textured Ti{sub 3}Al-Nb alloys usually exhibit anisotropic superplasticity and the degree of anisotropic superplasticity decreases as the strain rate decreases. In this research, the anisotropic superplasticity of the Ti-25Al-10Nb alloy at various deformation temperatures are presented and discussed. It is also attempted to describe the effect of the deformation temperature on the anisotropic superplasticity by the superplastic model of grain boundary sliding.