Using growth rate method, biological activities of 20 water extracts from 20 different plants were assayed against Colletotrichum gloeosporioides and Agaricodochium camellia Liu. The results show the inhibition rates of the extracts of Syzygium aromaticum, Scutellaria altissima L, Aloe Vera, Lonicera japonica Thunb, Andrgraphis paniculata are more than 60%. The best inhibition effects was S. aromaticum, respectively 96.2% and 98.2%. The toxicity test indicates that the EC50 of S. aromaticum and S. altissima L extracts and the mixture at the 1:1, 1:2, 1:5, 2:1, 5:1 volume ratio against C. gloeosporioides and A. camellia are, respectively ,4.2 and 3.68mg/ml,4.52 and 6.90 mg/ml,5.28 and 5.33 mg/ml,5.84 and 7.01 mg/ml,4.89 and7.01 mg/ml,5.24 and 6.11 mg/ml,4.77 and 5.65mg/ml. Synergistic interaction values are >0.5 and <1.5.