Nanoporous Ti alloy foam was prepared by dealloying from Ti-6Al-4V with low Al content in NaOH solution. The dealloying behavior for these systems was characterized using both dynamic polarization and potential hold measurements. The results indicate that the critical potential values for these system is 0.6 V. Potentials hold within the vicinity of the critical potential displays rapid decaying currents. With potential hold at 2.1 V, current intensities rapidly reach the peak and then show a constant. It is ascribe to Al sustain dissolution