Abstract The double sodium and iron phosphate Na 3Fe(PO 4) 2 was synthesized and studied by the XRD method, the second harmonic generation technique, and Mössbauer and IR spectroscopy. The compound crystallizes into a monoclinic system (space group C2/ c) with unit cell parameters a=9.0736(2) Å, b=5.0344(1) Å, c=13.8732(3) Å, β=91.435(2)° and is found to be related to the K 3Na(SO 4) 2 structure type. The crystal structure was determined by Rietveld analysis ( R wp=5.86, R I=2.03). Iron cations occupy the M (Na) position while sodium cations occupy the X (K) and Y (K) positions of the glaserite-like structure. Mössbauer spectroscopy shows the presence of high-spin Fe 3+ in octahedral coordination.