To study antibacterial activity of Chinese herbs as Scutellaria baicalensis Georgi，Coptis chinensis Franch，Rhus chinensis Mill，and so on，and their double-compounds, minimum inhibitory concentration (MIC) of single Chinese herb and the compounds against twelve pathogenic bacteria from eels were measured by agar dilution method. The results showed that ten kinds of Chinese herbs had antibacterial effect in different extent on the twelve bacteria. Rhus chinensis Mill had the best antibacterial activity, followed by Rheum palmatum Linn and Punica granatum Linn, and Equisetumra mosissimum Desf had the smallest antibacterial activity. Fifteen combinations had synergism antibacterial effects against pathogenic bacteria. Compared to single Chinese herb, antibacterial activity of almost all compounds had increased. The fractional inhibitory concentration (FIC) index of ＜1, was detected in 68.3% of the compounds, and FIC index of ≤0.5 was detected in 26.0% of the compounds. The study also indicated that rational use of Chinese herbal compounds not only can increase drug antimicrobial efficacy, but also can significantly reduce the concentration of Chinese herbs in the compounds.