Reaction of the Schiff base, 1-(4-methylimidazol-5-yl) phenylhydrazonopropane-2-one oxime (LH), with copper(II) perchlorate hexahydrate and copper(II) nitrate trihydrate in a 1 : 1 M proportion in methanol affords [Cu2L2(H2O)(ClO4)](ClO4) (1) and [Cu2L2(H2O)2](NO3)2] (2) in moderate yields. Both 1 and 2 have been characterized by elemental analysis, ESI-MS, FT-IR, UV–vis absorption spectroscopy, EPR, electric conductivity, and magnetic susceptibility measurements. The X-ray crystal structures of 1·CH3COCH3 and 2 have been determined. Both compounds are dinuclear copper(II) complexes, with each copper μ2-bridged by two oxime ligands in a μ2-η1,η2 fashion. Variable temperature magnetic studies on 1 and 2 show that both compounds are dominated by an antiferromagnetic coupling through the oxime bridges.