Six extracts-based natural antimicrobials were evaluated for their ability to inhibit the growth of Escherichia coli O157:H7, Escherichia coliNRRL3008 and Salmonella sp. Degree of inhibition was determined by the disk-diffusion assay. Results revealed the inhibitory effect of extracts (Without dilution and the same volume).Garlic extract had the strongest effect against E.coli NRRL3008 (24.00mm), Escherichia coli O157:H7 (22.00mm) and Salmonella sp. (18.00mm). Clove extract had stronger action against E. coli O157:H7 (35.00mm), E. coli NRRL.3008 (27.00mm) than Salmonella sp. (23.00mm). The most powerful effect of ginger extract was against E. coli O157:H7 (30.00mm), E.coli NRRL.3008 (26.00mm) followed by Salmonella sp. (22.00mm). E. coli O157:H7 (28.00mm) and E. coli NRRL.3008 (23.00mm) were strongly influenced by cardamom extract. Cinnamon extracts effective action against E. coli O157:H7 (31.00mm) followed by E. coli NRRL3008 (28.00mm) than Salmonella sp. (23.00mm). Rosemary extract strongly affected against E. coli NRRL3008 (25.00mm), E. coli O157:H7 (23.00mm) and Salmonella sp. (22.00mm). Extract mixture (clove, cinnamon and ginger) at level of 0.6% had stronger effect against E. coli O157:H7 (36.00mm), followed by E. coli NRRL3008 (34.00mm).The effectiveness of the ethanolic extracts against the growth of E. coli O157:H7 during 7 days of storage period at 37ºC followed the order: ginger > cinnamon > rosemary > cardamom > garlic> clove. It can be concluded that natural extracts of clove, cardamom, cinnamon, rosemary, ginger and garlic differ in their inhibitory activity against Escherichia coli O157:H7, Escherichia coli NRRL and Salmonella sp.so, these natural extract could be considered as natural food preservatives against pathogenic toxic bacteria and generally recognized as safe.