The creep resistance of SP700 (Ti-4.5Al-3V-2Mo-2Fe) is superior to Ti-6-4 (Ti-6Al-4V) at 500 A degrees C under a constant load corresponding to an initial stress of 100 MPa. The beta phase grains in the SP700 alloy prefer to orient along the loading axis in contrast to the Ti-6-4 alloy. The grain growth occurs during the stress drop incubation period. The observation of different amounts of negative creep/anelasticity upon loading is closely associated with the difference in the amount of grain/subgrain coarsening.