The full molecule of the binuclear title compound, [Cd2Cl2(C6H8O4)(C6H8N2)2(H2O)2], is generated by the application of a centre of inversion located at the middle of the central CH2—CH2 bond of the adipate dianion; the latter chelates a CdII atom at each end. Along with two carboxylate-O atoms, the CdII ion is coordinated by the two N atoms of the chelating benzene-1,2-diamine ligand, a Cl− anion and an aqua ligand to define a distorted octahedral CdClN2O3 coordination geometry with the monodentate ligands being mutually cis. The disparity in the Cd—N bond lengths is related to the relative trans effect exerted by the Cd—O bonds formed by the carboxylate-O and aqua-O atoms. The packing features water-O—H...O(carboxylate) and benzene-1,2-diamine-N—H...Cl hydrogen bonds, leading to layers that stack along the a-axis direction. The lack of directional interactions between the layers is confirmed by a Hirshfeld surface analysis.