The extracts from 36 kinds of Chinese Taibai herbs (CTHs) were obtained with the help of methanol and tested for antibacterial activity against four bacteria and two fungi inhibition through methods of inhibition zone, MIC and MBC. Then, the antibacterial mechanism of the extracts from CTHs was studied based on the growth curve and cell membrane permeability. The results showed that the best antibacterial activity against S. aureus and B. cinerea was the Notholirion hyacinthinum (Wils.)Stapf and the best activity against P. aeruginosa and E. coli was Cynanchum wilfordii (Maxim.) Hems L. The antibacterial mechanism of two CTHs were against four pathogen is as follows: drugs cause a decrease in the number of cell divisions in logarithmic phases and induce the voids of cell walls to become, thus the materials in the cell to leak out.