X-ray powder diffraction data for five new bismuth yttrium gadolinium oxide compounds synthesized by solid state reaction method are reported. The unit cell dimensions were determined from X-ray diffraction methods, using CuK alpha radiation, and evaluated by indexing programs. The cubic phase was the sole crystalline phase detected by X-ray diffraction analysis in Bi0.88Y0.06Gd0.06O1.5, Bi0.88Y0.08Gd0.04O1.5, Bi0.82Y0.09Gd0.09O1.5, Bi0.82Y0.12Gd0.06O1.5 and Bi0.82Y0.06Gd0.12O1.5 samples with lattice constants of a=5.5371(1) angstrom, a=5.5368(1) angstrom. a =5.5303(2) angstrom, a=5.53487(8) angstrom, and a=5.5279(1) angstrom, respectively. The results are in good agreement with those reported for bismuth yttrium oxide (Bi0.75Y0.25)O-1.5 (PDF 01-084-1450). (C) 2008 International Centre for Diffraction Data.