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The Gd 2 (WO 4 ) 3 :RE 3+ compounds (where RE 3+ = Sm and Tb) were prepared by the Pechini and ceramic methods and characterized by X-ray diffraction and infrared spectroscopy. These rare earth materials present high orange (Sm 3+ -compound) and green (Tb 3+ -compound) luminescence intensity under UV radiation. The excitation spectra of these compounds presented broad bands arising from ligand-to-metal charge transfer (O→W and O→RE 3+) and narrow bands from 4f-intraconfigurational transitions. The excitation spectra of Tb 3+ system also exhibit broad bands attributed to the interconfigurational transition (4f-5d). The emission spectra exhibited the , respectively, while a broad band assigned to the LMCT (O→W) is observed when the excitation is monitored on the O→W LMCT state around 270 nm. The experimental intensity parameters η Sm and η Eu present similar behaviors, suggesting that the Sm 3+ ion is in a highly polarizable chemical environment with similar covalent character of the metal-donor atom interaction to the tungstate doped europium system. The cross-relaxation process from the 5 D 3 to the 5 D 4 levels of the Gd 2 (WO 4 ) 3 :Tb 3+ system has been also reported.