In order to look for Trichderma strains which have inhibiting effects on Cytospora chrysosperma, total 29 domestic and foreign Trichderma strains were screened by confrontation culture and growth rate method. The physiological ecology characteristics and taxonomic statuses of the screened highly efficient antifungal strains were studied. The results showed that the n-butanol extract from T-33 fer- mentation liquid showed the highest inhibition rate （94.2%） against mycelial growth, and its inhibition rate against spore germination was up to 100%. For the growth of T-33 strain, the optimum carbon source was glucose with optimum content of 3% （g/L）; the optimum nitrogen source was soy four with optimum content of 0.02% （g/L）; the optimum initial pH of culture medium was 6; the optimum culture temper- ature was 25 ℃. The 18S rDNA sequencing results showed that the full length of ITS sequence was 583 bp, and the T-33 strain was verified as Trichoderma viride.
