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Background and Objective: Ruta graveolens is a plant used in traditional medicine with variety of therapeutic effects. This study was done to evaluate the antimicrobial effect of hydro and alcoholic extracts of Ruta graveolens on 8 species of pathogenic bacteria. Methods: In this descriptive study, standard strains of Enterococcus faecalis, Staphilococcus aureus, Staphilococcus epidermis, Strptococcus pneumonia, Escherichia Coli, Klebsiella pneumonia, Salmonella typhi and Enterobacter Cloace were obtained from Iranian institute of scientific and industerial research center. The effect of hydro and hydroalcholic extracts of Ruta graveolens on the growth of bacteria was determined by disc diffusion and serial macro dilution methods. Minimum inhibitory concentration (MIC) for each extract was determined and the findings were compared with 8 common antibiotics including Co-trimoxazole, Oxycycline, Vancomycin, Erythromycin, Furazolidon, Tetracycline, amoxicillin / clavulanic acid and Ampicillin/sulbactam. Results: Hydro and hydroalcoholic extracts of Ruta graveolens did not show any inhibitory effect on growth of the pathogenic bacteria even in the presence of high concentration (3mg/ml). Conclusion: The extracts of arial organs of Ruta graveolens had no inhibitory effect on growth of the common human pathogenic bacteria.