For high-strength titanium VT1-0, the ultrafine-grained structure of which was obtained by mechanical-thermal treatment using the methods of helical and longitudinal rolling followed by annealing to relieve stress of the first kind. The effect of long - term loading in the creep mode at elevated temperature on the size and shape of grains has been studied. A similar study was previously carried out for recrystallized coarse-grained titanium transferred from the ultrafine-grained state by isothermal annealing. Based on the data obtained in the work and the previous results of the authors, the factors affecting the mechanical stability (durability) of ultrafine-grained metals obtained under severe plastic deformation were analyzed.