The emergence of multi-resistant bacteria (BMR) represents a major health issue in the world. Among these bacteria, the most frequent encountered are those expressing a beta-lactamases (ESBL) extended-spectrum. The implementation of an alternative therapy represents the only solution to combat this health risk. The aim of this study is to investigate the bacterial diversity, antimicrobial resistance, types of beta-lactamases and to evaluate the antibacterial effect of the extract of Atriplex halimus on pathogenic multidrug resistant bacteria isolated from clinical infection and food samples. 13 pathogenic strains were isolated from different samples (5 Staphylococcus aureus, 5 E.coli, 2 Salmonella sp and 1 Clostridium sp) respectively. All isolates strains are Beta-lactamase producing. The three extracts from Atriplex hamilus, essential oil, hydrometanolic and acetate have a low yield linked to the characteristics of the plant itself. The extracts showed a higher antibacterial activity. The essential oil exerted an antagonist effect on all pathogens strains with 200μl/ml while hydrometanolic and acetate extract showed an inhibitory effect with a concentration of 300 mg/ml according to the tested strain. There results suggested that the extracts from Atriplex hamilus could be a potential alternative treatment of multidrug resistant bacteria.