The present invention relates to a technique, a method, and a composition for controlling plant pathogens comprising a Bacillus amyloliquefaciens KBC1004 strain and a culture medium thereof as active ingredients. Particularly, the Bacillus amyloliquefaciens KBC1004 strain and the culture medium thereof of the present invention have excellent antifungal activity against various plant pathogens such as Rhizoctonia solani AG-2-2(IV) causing turfgrass diseases, Botrytis cinerea causing gray mold rot, Colletotrichum acutatum causing chili pepper anthracnose, Colletotrichum gleosprodes causing sweet persimmon anthracnose, Rhizoctonia cerealis causing yellow patch, Rhizoctonia solani AG-1(1A) causing brown patch, Sclerotium rolfsii causing southern blight, and Phytophthora drechsleri causing kiwifruit phytophthora blight, so that they can be efficiently used as an eco-friendly composition for controlling plant pathogens.