Abstract: Flavonoid extract of Cyclocarya paliurus leaves is used in the preparation of antibacterial drugs and/or antibacterial agents against the bacteria that are resistant to conventional antibiotics. Experiments have proved that the flavonoid extract of C. paliurus leaves has obvious killing effect on methicillin-resistant Staphylococcus aureus strains, which provides a potential resolution to the problem that methicillin-resistant S. aureus strains are resistant to most beta-lactam antibiotics.