In the title structure, [Pb(C(5)H(3)N(2)O(2))(2)](n), the Pb(II) ion is six-coordinated by two pyridazine-3-carboxyl-ate ligands via N and O atoms, with the carboxyl-ato O atoms acting as bidentate and bridging adjacent Pb(II) ions, giving rise to catenated mol-ecular ribbons propagating along the a-axis direction. The ribbons are connected by C-H⋯O hydrogen bonds and van der Waals inter-actions.