The hemolmyph and whole body of insect, Bombyx mori, Allomyrina dichotoma and Neotocia brevitarsi, conspicuously inhibited the mycelial growth of several plant pathogenic fungi. The hemolymph of 1087 strain among the 16 strains of B. mori has inhibition activities against the 3 species of fungi, Alternaria panax, Collctotrichum gloeosporioides, and Pyricularia oryzae. The whole body of B. mori was more effective than the hemolymph as a inhibitor on fungi growth. The antifungal activity of B. mori was variable to the fungi species. In addition, A. dichotoma and N. brevitarsi showed antifungal activities against the same fungi as did B. mori. These data showed that the insect has potent antifungal activity. Whereas, the level of activities were differ according to the fungal species. This finding underlines that the possibility of the insect can be use of the agent as a inhibitor against the plant pathogenic fungi.