In the title compound, [In(C8H4O4)(OH)(H2O)]n, the coordination of the InIII ion is composed of six O atoms from three dianionic benzene-1,2-dicarboxylate ligands, two hydroxyl groups and one coordinated water molecule in a distorted octahedral geometry. The In3+ ions are linked by the hydroxyl groups to form zigzag In-OH-In chains, which are further bridged by the benzene-1,2-dicarboxylic acid ligands to generate a two-dimensional layered structure featuring three types of rings (six-, 14- and 20-membered). Hydrogen bonds between the water molecule and a carboxylate O atom, and between the hydroxyl group and a carboxylate O atom, are observed within the layers. In the crystal packing, there are pi-pi stacking interactions between the benzene rings of adjacent layers, with a centroid-to-centroid distance of 3.668 (3) A and a dihedral angle of 4.8 (2) degrees.