Two monomeric ternary complexes of (+) -(S)-2-(6-Methoxynaphthalen-2-yl) propanoic acid (Naproxen) and N-(4-Nitro-2-phenoxy phenyl) methanesulfonamide (nimesulide) were prepared by the reaction of CuCl2⋅2H2O and N,N,N′,N′-tetramethylethylenediamine (tmen) in the presence of sodium hydroxide. Both complexes were characterized by the elemental combustion analysis, UV-visible and FT–IR spectroscopy, thermal analysis, and single-crystal X-ray diffraction. From the crystal structure of complexes, it is evident that each copper (II) ion is six-coordinate and is bonded to chelating tmen. The complexes of copper (II) and TMEDA with Naproxen and Nimesulide were in the ratio 1:2:1. The Complexes were blue in color and their melting points were recorded as 196 °C and 220 °C respectively. UV- Visible spectra of complexes exhibited three absorptions. The intense absorption band at higher energy was 250 nm and 300nm for both complexes respectively. Both complexes were found to possess antibacterial properties against four strains, including Staphylococcus aureus, Bacillus spizizenii, Escherichia coli, and Klebsiella pneumonia.Keywords: Synthesis, Cu(II) complexes, Naproxen & Nimesulide, TMEDA.Citation: Tehzeeb, M., Batool, S.S., Hadyait, M.A., 2020. Synthesis and Characterization of Cu(II) Complex with NSAIDs (Naproxen and Nimesulide) and Tetramethylethylenediamin. Int. J. Nanotechnol. Allied Sci., 4(1): 1-8.