In the title compound, [Cd(C10H9N4O2S)2(C12H12N2)]·2C3H7NO, the CdII ion lies on a twofold rotation axis, is six-coordinated by N atoms, and displays a trigonal–prismatic geometry arising from the two sulfadiazinate ligands and one 4,4′-dimethyl-2,2′-bipyridine ligand. Both ligands are bidentate and coordinate via their N atoms. The O and carbonyl C atoms of the dimethylformamide molecule show disorder and were modelled with two different orientations and with site occupancies of 0.584 (10):0.416 (10). The geometry around the sulfadiazine S atom is distorted tetrahedral. The crystal structure involves N—H⋯O hydrogen bonds which link molecules into a three-dimensional network. Weak C—H⋯O hydrogen bonds are also observed.