The aim of this work was to investigate chemical compositions and antibacterial properties of several Iranian essential oils (EO) bearing plants including Satureja hortensis, Trachyspermum ammi, Mentha piperita, Lippia citrodora, and Foeniculum vulgare. Antibacterial properties of EOs against Pseudomonas putida, Enterobacter aerogenes, Salmonella typhi and Escherichia coli as Gram-negative bacteria and also Leuconostoc mesenteroides subsp.mesenteroides, Listeria monocytogenes, Bacillus cereus and Staphylococcus aureus as Gram-positive bacteria were determined by Disk diffusion agar, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). The chemical composition of EOs was characterized using gas chromatography and gas chromatography/mass spectrometry (GC/MS). The results of EOs analysis indicated that there are different compounds in each EO giving them different characteristics. According to the results, each EO has a different potential to inhibit the growth of bacteria. Among the EOs studied, T. ammi and S. hortensis revealed the strongest antibacterial activity whereas F. vulgare showed the weakest antibacterial activity.