For thousands of years, Punica granatum L. has been used in traditional medicine all over the world and predate the introduction of antibacterial drugs. The aim of the present study was to investigate the antibacterial activity of tannins , aqueous and methanolic extracts of Punica granatum L. bark obtained by extraction and maceration. The different extracts of Punica granatum L. bark have been tested for antibacterial activity against Gram-positive bacteria (Staphylococcus aureus, Listeria monocytogenes, Enterococcus faecalis, Bacillus stearothermophilus) and Gram-negative bacteria (Escherichia coli, Klebsiella pneumonia ,Pseudomonas aeruginosa) by disc diffusion method. The tannins and the methanolic extract showed the strong in vitro, tannins antibacterial activity against Listeria monocytogenes with zone inhibition of 25.80 mm. However, the results tests by disc diffusion method revealed the effectiveness of methanolic extract against Gram-positive bacteria (Staphylococcus aureus and Bacillus stearothermophilus) with diameter zone of inhibition varying with 23mm and 22 mm respectively.