The chemistry of thiosemicarbazone complexes has received much attention owmg to their significant biological activities [1] and medical properties [2]. We repo1i here the synthesis, stmcture and biological studies of a new copper(II) coordination compound with 8-quinolinealdehyde 4-(o-fluorophenyl)thiosemicarbazone. The organic ligand (HL) was prepared by condensation of equimolar amount of 8- quinolinealdehyde with 4-(o-fluorophenyl)tiosemicarbazide, confomed by elemental analysis and IR spectral studies. The copper(II) complex was prepared using the reaction of copper salt Cu(NO3)2·3H2O with ligand in 1 : 1 molar ratio. The X-ray single c1ystal investigation show, that c1ystal is built from binuclear neutral units [CuL(NO3)h (Fig. 1). The organic ligand L- is coordinated as tridentate NNS chelating monoanion and fonns with Cu(II) two coplanar rings: six-membered CuN2C3 and five membered CuSN2C. Coordination of metal is completed up to six by two O atoms of NO3- anion and S bridging atom of the neighbour complex unity, and fonns a disto1ied tetragonal bipyramid around the central atom. The interatomic distances: Cu-S 2.276(1), Cu-N are 1.948(4 ) and 2.049(4), Cu­O(2) is 1.991(4) A (the base of polyhedron) and Cu-0(1) and Cu-S are 2.693(2) and 2.893(1) A, respectively (the apex), are close to the values found for them in other complexes. The ligand and the copper complex were tested for their antibacterial activity. The results of antimicrobial experiment evidently show that the activity of the copper(II) complex is more pronounced than for the free organic reagent. The complex was found to be active against Staphylococcus aureus and Escherichia faecalis.