The present study investigated the potential antimicrobial activities of the leavecrude extracts of the moringa species, M. peregrina in comparison to those of M. oleifera. Most of the previous studies on antimicrobial, antifungal, and antioxidant activities were concentrated on (M. oleifera) because of its prevalence in the poor areas in Africa and Asia where most of the people in the rural areas search for edible natural food resources. However, M. peregrina, the tree that grown as a wild plant in the Arabian desert has received less focus and no details studies were traced on its chemical composition and biological activity. Results indicated that, M. peregrina proved to have antimicrobial activities against five bacterial species but this activity was less than that observed by M. oleifera. The genetic relations between the three Moringa species (M. peregrina, M. oleifera and M. ovalifolia were studied using RAPD analysis. M. peregrina showed higher genetic similarity with M. oleifera (49%) than that with M. ovalifolia (44%). The results of this study indicated the possibility of using the leave extract of the Arabian moringa (M. peregrina) as a source of antibacterial compounds for treatment of infections caused by multi-drug resistant (MDR) bacterial pathogens.