and objectives: As much as people become aware of the dangerous side effects of synthetic antibiotics, the demand for natural alternatives to these drugs increases. Natural ingredients, lower risk of complications and even have beneficial side effects. The aim of this study was to determine the antibacterial effect of herbs Reum ribes L and hyssop Hyssopus officinalis is on some pathogenic bacteria. Methods: After collecting and confirming the scientific name, the methanolic extract of R. ribes

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... L. and H. officinalis plants was prepared and the antimicrobial effects of the extracts by agar well diffusion and disk diffusion , as well as the determination of The minimum bactericidal concentration and the minimum inhibitory concentration (MIC / MBC) were dilution test on Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. Results: The highest growth inhibitory zone in S. aureus, B. cereus, P. aeruginosa, and E. coli at concentrations of 400 mg / ml, respectively, in the disc method of 13.21, 13.41, 11.2 and10.74 mm and the well method, respectively 13.64, 13.11, 10.67 mm, and 9.38 mm for the R. ribes L extract, and the disc method of 11.74, 10.2, 10.71, and 9.1 mm, and the well method of 12.41, 11.6, 10.2, and 9.9 respectively. 4.3 mm was observed for H. officinalis extract. The results of MBC / MIC showed that the extract of medicinal plants had the highest susceptibility to B. cereus bacteria and the least susceptibility to E. coli. Conclusion: R. ribes L. and H. officinalis plants have significant inhibitory effects on the growth of pathogenic bacteria in vitro. Therefore, it can be expected that these extracts can be used for the treatment of bacterial infections and are a good alternative to the usual chemical treatments for the treatment of infections.