Abstract <p>Terbium-doped lanthanum metaphosphates La_{1–<i>х</i>}Tb_<i>х</i>P₃O₉ (<i>х =</i> 0.05, 0.1, 0.2, 0.3, 0.4), promising as inorganic luminophors have been prepared by extraction–pyrolytic method at lower temperature as compared with the known methods. Crystal structure and optical properties of obtained samples have been studied by X-ray powder diffraction, IR and luminescence spectroscopy; unit cell parameters have been calculated. Compounds with rhombic structure (space group <i>C</i>222₁) have been obtained in the temperature range of 500–900°С. All unit cell parameters linearly decrease on introduction of terbium in lanthanum metaphosphate. Compounds La_{1–<i>х</i>}Tb_<i>х</i>P₃O₉ exhibit strong luminescence in the region of 450–650 nm. A sample of La_0.8Tb_0.2P₃O₉ prepared over 1–<i>h</i> annealing at 900°C displays the maximal luminescence intensity.</p>