Copper(II) complex [Cu(dmbt)2(H2O)](ClO4)2 (1) was prepared from the reaction of copper(II) perchlorate hexahydrate with 2,2'-dimethyl-4,4'-bithiazole (dmbt) ligand in methanol at ambient temperature. The complex was quantitatively and qualitatively characterized by elemental analysis, absorption and infrared spectrometries. Complex [Cu(DMSO)5](ClO4)2 (2) was also synthesized from the recrystallization of complex [Cu(dmbt)2(H2O)](ClO4)2 (1) in the dimethyl sulfoxide solvent through a slow evaporation of the solvent at room temperature. The compound was characterized by elemental analysis, infrared spectrometry and single-crystal X-ray diffraction. Crystallographic analysis of this complex revealed that the single crystal of this compound is crystallized in the trichlinic crystal structure, with the space group Pī and cell dimensions of a = 10.894(3), b = 10.853(4) and c = 12.947(5)Å as well as the angle β = 111.95 (3)°.Interestingly, this compound is the first example of 5-coordinated copper(II) complex with dimethyl-sulfoxide ligand in a square pyramid structure. Manuscript profile