The title compound, [Li2(C12H6O4)(H2O)2] n , crystallizes with one half of the molecular entities in the asymmetric unit. The second half is gererated by inversion symmetry. The crystal structure has a layered arrangement built from distorted edge-sharing LiO3(OH)2 tetra-hedra parallel to (100), with naphthalenedi-carboxyl-ate bridging the LiO3(OH)2 layers along the [100] direction. Hydrogen bonding between the water molecule and adjacent carboxylate groups consolidates the packing.