The synthesis and physico-chemical characterization of a novel organic-inorganic hybrid material, 1-(2,5-dimethylphenyl)piperazine-1,4-dium tetrachloridocuprate(II), have been reported. This compound crystallizes in the monoclinic system with the space group of P 2 1 /n and cell parameters a = 9.833(3), b = 16.337(2), c = 10.452(3) Å, β = 102.13(4) • , Z = 4 and V = 1641.5(7) Å 3. In the title salt, (C 12 H 20 N 2)[CuCl 4 ], the geometry of the CuCl 2− 4 ion is intermediate between tetrahedral and square planar. In the atomic arrangement tetrachlorocuprate anions and the piperazine-1,4-dium cations are held together via N-H.. .Cl and C-H.. .Cl to give a 1-D hybrid chain running along the a-axis. The six-membered piperazinedium ring adopts a chair conformation. The vibrational absorption bands were identified by infrared spectroscopy. Magnetic measurements reveal that moderate antiferromagnetic (AF) Cu-Cu interactions dominate in the title compound.