The (La, Eu) co-doped YVO 4 with nano-crystal phosphors were prepared using a sol–gel method. The X-ray diffraction profiles show that all of the peaks are attributed to the YVO 4 phase when co-doped with the (La 3+ , Eu 3+ ) ions. The intensities of the diffraction peaks decreases when the La 3+ ion concentrations increase. In addition, under an excitation of 318nm, the 5 D 0 → 7 F 2 transition intensity increased with increasing the La 3+ ion concentration, and increased about five with the 15mol% of La 3+ ion doping. This is caused by the large difference in ion radius between the La 3+ and Y 3+ ions, which leads to a distorted lattice and a local nonuniform strain in the vicinity of the Eu 3+ ions when La 3+ ions substitute Y 3+ ions in the (Y 0.9−x La x )Eu 0.1 VO 4 system. The bright red emission of the (Y 0.9 Eu 0.1 )VO 4 phosphor has the CIE chromaticity coordinates of (0.66, 0.34) with 15mol% La 3+ ion doping, which is very close to the NTSC system standard red chromaticity coordinates of (0.67, 0.33).