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The bars of Ti-53Nb alloy were prepared by room temperature Equal Channel Bending Channel Deformation (ECAP) with cold rolling and rotating and followed by forging combined deformation method. The evolutions of microstructure and b-crystal growth were systematically studied by metallographic microscope (MM), scanning electron microscope(SEM) and uniaxial tensile test after preparing process. The effects of work hardening and fine grain strengthening were analyzed with dislocation strengthening theory and Hall-Petch theory. The results show that the tensile strength increases from 380MPa to 553MPa before and after deformation and heat treatment, it shows that the preparing technology enhances significant tensile strength and elongation with the increase ratio of 45.53% and 16%, respectively. The growing speed of b-crystal is accelerated with increasing solid solution temperature, and the grain size dependence of strengthen follows Hall-Petch equation. The microstructure exhibits uniform with fine iso-axial shape by annealing at 700℃for 60 mins, which can match the requirement of strong plastic characteristics for the application.