The [Ag(3-Py-CHO)2NO3] complex, where (3-Py-CHO); Nicotinaldehyde (3-pyridinecarboxaldehyde), was synthesized and characterized by means of elemental analysis, various spectroscopic techniques (FT-IR, 1H NMR, PL) and DFT calculations. Besides, the silver metal, Ag(I), was coordinated with two organic ligand molecules in the complex. The optimized molecular geometry, vibrational frequencies, electronic properties, such as frontier molecular orbitals energies as well as the molecular electrostatic potential (MEP) were employed by utilizing the DFT theory. Calculated results and experimental data for the IR, 1H NMR and PL spectra indicated a solid interrelated consistency. Antimicrobial studies have been conducted with the ligand and silver(I) complex against various gram +ve, gram -ve bacterial species. Antibacterial activity of the ligand and its Ag(I) complex were tested againsts elected bacteria by minimum inhibitory concentration (MIC) and discdiffusion method. The Ag(I) complex reflected good activity in the range of 15.6-125 mu g /mL against all bacteria tested, while the ligand how better activity in the range of 15.6-62.5 mu g/ mL as MIC values. The complex indicated zone of inhibition values in the range of 10-30 mm (100 mu g /mL). The results pointed out that the Ag(I) complex and ligand were more effective against bacteria.