Abstract: The effects of six fungicides on the growth of Trichderma sp. were tested. The results showed that the different kinds and treatment concentrations of fungicides on the growth of Trichderma sp. had significant differences. Thiopanate methyl、Carbendazin and Chlorothalonil in 200、400、600、800、1000 times solution gave full inhibiting effects on growth of Trichderma sp., with 100% of the inhibiting rates. Vinclozolin and Metalaxyl in 200 times solution showed low inhibiting rates, with 89.7% and 79.6% respectively. Dithane M-45 in 200 times solution showed the lowest inhibiting rates , with 55.3%.