Avicennia marina is a commonly found mangrove species in coastal regions, and is known for its medicinal properties. In this study, the antibacterial and antifungal activities of ethanolic extract of Avicennia marina leaves were evaluated against MDR microorganisms. The antimicrobial activity of the extract was assessed against a range of bacterial strains, including Salmonella sp. (MDR), Klebsiella sp. (MDR), Pseudomonas sp. (MDR), Acinetobacter sp. (MDR), Staphylococcus aureus as well as the fungal strain Candida albicans (ATCC 10231), Candida parapsilosis (ATCC 22019). The results showed that the leaf extracts of Avicennia marina exhibited significant antimicrobial activity against all tested MDR microorganisms. The phytochemical content of the plant includes many bioactive compounds - flavonoids, tannins, and alkaloids, which may be responsible for the observed antimicrobial activities. These findings suggest that Avicennia marina may be a potential source of natural antimicrobial agents, which could be used to develop new drugs for the treatment of resistant bacterial and fungal infections. Further studies are needed to identify and isolate the active compounds responsible for the observed activity and to evaluate their efficacy and safety in vivo.