The calculated crystallite sizes of (La(1-x)Y(x))(0.94)Tb(0.06)PO4 (0 < or = x < or = 1.0) phosphors ranged from 37-39 nm. Annealed (La(1-x)Y(x))(0.94)Tb(0.06)PO4 (0 < or = x < or = 1.0) phosphors showed a smooth, regular, and spherical morphology. Strong excitation peaks were appeared at 226 and 270 nm for all the phosphors. These were caused by the crystal splitting of 7D and 9D of 4f75d1 configuration in Tb3+, respectively. The characteristic emission peaks were observed at 489, 543, 585, and 621 nm, which were caused by the 5D4-7F(j) (j = 6-3) transitions of Tb3+, respectively. The emission intensity at 543 nm increased with an increase in Y content up to 0.5 and then decreased for a higher Y content.