The asymmetric unit of the title salt, C(4)H(12)N(2) (2+)·2C(7)H(4)NO(4) (-) or pipzH(2) (2+)·2(py-2,3-dcH(-)), prepared by a reaction between pyridine-2,3-dicarboxylic acid (py-2,3-dcH(2)) and piperazine (pipz), contains a monoanion and half of a centrosymmetric dication. The anionic fragment individually has two intra-molecular hydrogen bonds, an almost linear O-H⋯O bond between two carboxyl-ate groups and a C-H⋯O bond between the aromatic ring and carboxyl-ate group. Other O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds are responsible for three-dimensional expansion of the structure.