Photoluminescence properties of NaBi(WO4)2 crystals were studied near liquid nitrogen temperatures. The excitation and emission properties were found to be similar to an iso-structural Scheelite PbWO 4. A metal-to-metal charge-transfer character (Bi3+→ W6+) is found responsible for the emission process. The thermal activation energy for quenching of the luminescence was found to be about 160 meV. © 2011 American Institute of Physics.