In the title polymer, [Cd(C(5)H(3)N(2)O(2))(NO(3))(H(2)O)](n), the Cd(II) atom is seven-coordinate in a distorted capped octa-hedral geometry by two N atoms of two different pyrimidine dicarboxyl-ate (pmc) ligands, three O atoms from three separate pmc ligands, and two O atoms of disordered nitrate anions or water mol-ecules. The Cd(II) atoms are bridged by the pmc ligands in a chelating/bridging bis-bidentate and chelating bidentate mode, forming sheets parallel to (20-1). The sheets are further linked into a three-dimensional supra-molecular network via classical O-H⋯O hydrogen bonds involving the nitrate anions and coordinating water mol-ecules. Intra-molecular O-H⋯O hydrogen bonding is also observed. The non-coordinating nitrate O atoms are disordered over two sets of sites with occupancies of 0.57 (7) and 0.43 (7).