The antibacterial activities of hot water, methanol and ethanol extracts of 5 plant extracts utilized in Palestine in popular medicine were studied. The dried extracts of Syzyium aromaticum (Myrtaceae) (seed), Cinnamomum cassia (Lauraceae) (cassia bark, Chinese cinnamon) (bark), Salvia offidnalis (Lamiaceaea) (leaf), Thymus vulgaris (Lamiaceaea) (leaf) and Rosmarinus offidnalis (Labiatae) (leaf) were tested in vitro against 4 bacterial species by disk diffusion and micro-dilution. The patterns of inhibition varied with the plant extract, the solvent used for extraction, and the organism tested. Methicillin-resistant Staphylococcus aureus (MRSA) and Bacillus subtilis ATCC 6633 were the most inhibited microorganisms. S. aromaticum extract was the most active against multi-drug resistant Pseudomonas aeruginosa and enterohemorrhagic Escherichia coli 0157 EHEC. The combinations of ethanolic extracts of S. offidnalis with R offldnalis and of R offidnalis with T. vulgaris on bacterial species tested exhibited a higher effect than that of any individual extract. Results of this kind herald the interesting promise of designing a potentially active antibacterial synergized agent of plant origin.