A gamma titanium aluminide alloy is provided, based on the intermetallic compound TiAl, in which the resulting alloy is characterized by high creep strength and environmental resistance at elevated temperatures in excess of about 650.degree. C., and as high as about 850.degree. C. The alloy achieves these desirable properties through limited and interrelated additions of chromium, niobium and tantalum, whose combined amount is established by a minimum amount necessary to achieve a desired level of oxidation resistance.