Ilmenite (FeTiO ) is an antiferromagnetic insulator with Néel temperature (T ) of 55 K. The magnetic structure of FeTiO is known to be easily frustrated by cation substitution. In the present study we tried to prepare the Ge-substituted FeTiO . The samples were prepared by the conventional solid state reaction technique under the controlled oxygen pressure. Formation of a single phase of FeTi Ge O with x=0.01 was confirmed by X-ray diffraction (XRD) method. The Ge-substituted FeTiO had a smaller lattice volume than that of un-doped one. SQUID magnetometer and Mössbauer spectroscopy measurements indicated that the Ge-substitution reduced the T slightly. Moreover the magnetic hyperfine fields of Ge-substituted FeTiO seemed to be increased in spite of the decreased magnetic moments. © 2010 IOP Publishing Ltd. 3 N 3 3 1-x x 3 3 N 3