Two new Cd(II) complexes, with the ligand 4'-(4-chlorophenyl)-2,2':6',2"-terpyridine (Clphtpy) formulated as: [Cd(Clphtpy)(NO3)2H2O] (1), and [Cd(Clphtpy)(N3)2]2 (2), have been synthesized and characterized by CHN elemental analysis as well as FT-IR, 1H NMR, absorption and emission spectroscopy, thermal analysis and analyzed structurally by X-ray single-crystal diffraction. The single crystal X-ray analysis showed that the coordination number in complex 1 and 2 were seven and six with N3O4 and N6 coordination sphere, respectively. The antibacterial activities of the synthesized complexes were tested against four gram-positive and four gram-negative bacteria. A biological study of the complexes indicated that the complex 1 exhibited very good activity against most of the tested bacteria and its activity was better than gentamicin as a standard antibiotic.