A- and B-site substituted double-perovskite Sr2CaMoO6 by Eu3+ have been synthesized using solid-state reactions and characterized by X-ray diffraction, Raman spectroscopy, and photoluminescence measurement. Raman spectra are used to identify the A- and B-site substitutions, because specific Raman peaks corresponding to different ions motion are sensitive to each situation. Raman data reveal that both the A- and B-site substituted solid solutions are formed. The photoluminescence intensity of the B-site substituted Sr2CaMoO6 is evidently higher than that of the A-site substituted phosphor. The WO6 group introduced into Sr2CaMoO6:Eu3+,Li+ acts as an energy obstacle to prevent energy transfer among MoO6 groups, leading to more energy being trapped by Eu3+, and a higher photoluminescence intensity is obtained. The phosphor with optimized composition Sr2Ca0.80Li0.10Eu0.10Mo0.10W0.90O6 shows a better luminescence intensity than the commercial phosphor Y2O2S:Eu under 395 nm excitations. (c) 2008 The Electrochemical Society.