en ميکروبيولوژي Microbiology پژوهشي Research <strong>Background:</strong> Due to increased bacterial resistance to common antibiotics, the tendency towards using herbal extracts is increasing. <em>Plantago major</em> L, <em>Plantago ovata</em>, <em>Lallemantia iberica</em> L, <em>Sinapis arvensis </em>L, and <em>Ficus carica </em>&nbsp;are widely used as herbal plants in traditional medicine. They were known to have a variety of therapeutic effects. The current study aimed to evaluate the antibacterial activity of hydroalcoholic extract of these herbs against some hospital-acquired infections.<br> <strong>Materials and Methods: </strong>Disk-diffusion antibiotic sensitivity testing, minimum inhibitory concentration, and minimum bactericidal concentration of hydroalcoholic extracts were applied to assess the antibacterial activity compared with tetracycline, as a control antibiotic.<br> <strong>Results:</strong> The results of this experiment showed that the L. iberica and S. arvensis extract had the greatest effect on Pseudomonas aeruginosa, Staphylococcus aureus, and Proteus vulgaris. All the tested medicinal plants had a high antibacterial effect on P. vulgaris, except P. ovata.<br> <strong>Conclusion: </strong>The results of this study show that the replacement of chemical drugs with herbal extract could be effective in the elimination of bacterial growth. Lallemantia iberica, Sinapis arvensis, Hospital-acquired infection, Antibacterial 133 138 http://rmm.mazums.ac.ir/browse.php?a_code=A-10-909-3&slc_lang=en&sid=1 Hassan Habibi h.habibi@pgu.ac.ir 10031947532846009066 10031947532846009066 Yes Department of Animal Science, Faculty of Agriculture and natural resource, Persian Gulf University, Bushehr, Iran. Noorsaadat Saajedi dr.h.habibi@gmail.com 10031947532846009067 10031947532846009067 No Department of Obstetrics and Gynecology, Iran University of Medical Sciences, Tehran, Iran Najmeh Ghahtan ghahtan1995@gmail.com 10031947532846009068 10031947532846009068 No Department of Plant Breeding, Faculty of Agriculture and natural resource, Persian Gulf University, Bushehr, Iran Saajedeh Habibi habibisara708@gmail.com 10031947532846009069 10031947532846009069 No Medical Student, Shahid Sadoughi University of Medical Sciences, Yazd, Iran