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The influence of the microstructure on the creep properties of a Ti–46.8Al–1Mo–0.2Si was studied by stress change tests in compression at temperatures ranging from 700 to 1000 8C. The material produced by arc melting exhibited a structure of coarse lamellar grains in the as-cast condition that transformed to an equiaxed near g microstructure after processing by hot extrusion at 1300 8C. The high temperature deformation data strongly depended on the type of microstructure present in the material. For each microstructure, deformation data were correlated by means of a conventional power law creep relation. The analysis showed an activation energy of about 400 kJ/mol for both microstructures. On the other hand, each starting microstructure showed a different stress exponent. TEM analysis of deformed samples allowed the correlation of the stress exponents to different mechanisms controlling deformation