Abstract: In order to look for the Trichderma strains which have inhibiting effects on Chtospora chrysosperma, 29 domestic and foreign strains were screened by methods of antagonistic culture and growth-inhibiting. The morphological characteristics and physiological characteristics and taxonomic status of efficient antifungal strain were studied. The results showed that the growth-inhibiting rate of the N-butanol extract extracted from the fermented liquid of strain T-33 was 94%, and inhibition rate of spore germination was 100%. The optimal C-source of strain T-33 was glucose and the optimal content was 3% (g/L). The optimal N-source of strain T-33 was soy flour and the optimal content was 0.02% (g/L). The optimal initial pH of culture medium was 6. The optimal culture temperature was 25℃. Through 18S rDNA sequencing and phylogenies analysis of T-33, the length of ITS sequence was 583 bp, strain T-33 was verified as Trichoderma viride.