The possibility to realize ultrafine grained(UFG) microstructure with a Ti alloy through intensive plastic straining (IPS) was explored. Formation mechanism of UFG was discussed. It has been shown that sub-micron grained Ti alloy could be obtained by compression below 750degreesC. Microstructural evolution included the process of dynamic recrystallization in alpha phases and precipitation-growth in beta phase. Deformation would not only enhance the precipitation and growth of beta phases, but also change the morphology of beta precipitates into equiaxed. UGF Ti-alloy was produced trough radial forging and isothermal rolling. A DB/SPF part was produced successfully by this kind of UGF Ti-alloy.