Spectral hole-burning has been observed in Eu3+ ion exchanged Na beta " -alumina. There are two types of persistent holes at different burning wavelengths: One is with a complex band shape and the other with a simple Lorentzian shape. The latter persistent hole, with a simple Lorentzian shape, can be burned up to 70 K for 90% exchanged sample of Eu3+ ions. This observed persistent hole is caused by a light induced local-structure change surrounding Eu3+ ions or the light-induced local motion of ions. The barrier height (potential energy) for the light-induced local motion of ions was determined from the analysis of the thermal decay-profile of the persistent hole, which was obtained from the so-called temperature cycling experiment. Two potential energies, which will be related to those for the ionic motion of the conduction ions through the conduction pass, were obtained.