In the title complex, [Ba(C(7)H(3)NO(4))](n), the coordination geometry around the Ba(II) ion can be described as a distorted bicapped trigonal-prismatic BaNO(7) arrangement. The pyridine-2,4-dicarb-oxy-lic acid ligands exhibit a new coordination mode. Adjacent metal centers are linked by the O atoms of the pyridine-2,4-dicarb-oxy-lic acid ligands, and then form a three-dimensional supra-molecular polymeric framework.