OBJECTIVE： To investigate in vitro antibacterial effect of extracts from Miao medicine Rubus multibracteatus leaves. METHODS： The aqueous extract and 80％ ethanol extracts from R. multibracteatus leaves were used to prepare solution with mass concentration of 200 mg/mL. Using ampicillin and fluconazol as positive control （50 mg/mL）， cup plate method was used to determine antibacterial effects of the extracts from R. multibracteatus leaves to Staphylococcus aureus， Staphylococcus epidermidis， Escherichia coli， Shigella dysenteriae， Proteus vulgaris， Candida albicans and Cryptococcus neoformans. The petroleum ether， acetic ether and n-butyl alcohol were used to extract 80％ ethanol extracts in turns. After obtaining relevant extracts （50    mg/mL）， cup plate method was used to investigate antibacterial effects of them to above 7 bacterial strains. The parts with antibacterial effects and bacterial strains sensitive to drug were screened. Micro-broth dilution method and agar culture medium plate method were used to determine minimum inhibitory concentration （MIC） and minimum bactericidal concentration （MBC）. RESULTS： The aqueous extract of R. multibracteatus leaves almost had no inhibitory effect while 80％ ethanol extract showed different degrees of antibacterial effect to tested bacterial strains， and it also had higher activity against 5 bacterial stains than 2 fungus. The ethyl acetate and n-butyl alcohol fractions of 80％ ethanol extracts showed good effect while the petroleum ether and water layer fractions had no antibacterial effect， and all the fractions of 80％ ethanol extracts showed no inhibitory effect on fungus. To 5 bacterial stains， MIC and MBC of 80％ ethanol extract were 6.25-12.5， 12.5-25 mg/mL， those of ethyl acetate fractions were 3.13， 6.25  mg/mL and those of n-butyl alcohol fraction were 3.13-6.25， 6.25-12.5 mg/mL， respectively. CONCLUSIONS： 80％ ethanol extract of Miao medicine R. multibracteatus leaves and its ethyl acetate and n-butyl alcohol fractions have obvious in vitro antibacterial effect to bacteria.