Effects on the bacteria gwoth of 96 kinds of crude drugs described in "Pen-Tsao-Kang-Mu" was investigated. Galla Rhois, Moutan Cortex Radicis, Aconiti Tuber, Euphorbiae Radix and PAeoniae Radix showed the antibacterial activity but Cnidii Rhizoma, Coicis Semen, Angelicae gigantis Radix, Asparagi Radix and Liriopes Tuber show the gwoth promoting action of all bacteria used in this experience. It can be seen that 10 kinds of crude drugs classified as poisonous plants inhibited the growth or had no effect by never promoted. 32 kinds of crude drugs as drugs acting on the gastrointestinal system showed antibacterial activity on E. coli $O_{55}$ and E. coli $O_{111}$. 18 kinds on inflammation showed antibacterial activity on Staphylococcus aureus and Sarcina lutea.