LaInO(3), a promising ion conductor for a holistic solid oxide fuel cell, was synthesized by a solid-state reaction method. The structure was refined by the Rietveld method using X-ray powder diffraction data. The structure of LaInO(3) is distorted by the in-phase and antiphase tilting of oxygen octahedra in the a(+)b(-)b(-) system of the InO(6) polyhedra. In the Pmna space group, the In atom lies on an inversion centre and the La atom and one of the O atoms lie on a mirror plane.