The local structure around the Nd3+ ions in 60%-exchanged sodium beta"-alumina was studied by X-ray absorption spectroscopy. The analysis of the Nd L3-edge experimental data shows that neodymium ions are mainly located near mid-oxygen (9d) sites. The local environment of Nd is slightly changed compared to crystallographic positions : the Nd-O(5) distance is shortened by 0.36 angstrom, while the Nd-Al (6c) is increased by 0.13 angstrom. The values of Debye-Waller factors of different coordination shells are discussed in terms of vibrational correlation.