In the title compound, (C4H8N3O)2[CdCl4], the asymmetric unit comprises two creatininium cations and one tetrachloridocadmate anion. Cd⋯O secondary bonding links one of the two imidazole rings and the anion into ion pairs. The free and bound cations form layers between which the [CdCl4]2− anions are sandwiched. The CdII atom adopts a distorted trigonal-bipyramidal geometry in which the Cd⋯O bond is axial. Intermolecular N—H⋯Cl hydrogen bonds form a two-dimensional network parallel to (001) which ensures the junction between creatininium cations and [CdCl4]2− anions.