In 2014, abnormal brown spots were observed on Hongro apples in fields in Gyeongsangbuk-do Province and during low-temperature storage. The spots were round, blight brown, and different from the symptoms of previously reported apple diseases. A fungal pathogen was isolated and cultured on potato dextrose agar, and it was morphologically similar to . A pathogenicity test showed the same brown spots on both wounded and unwounded Hongro and Fuji apple cultivars. RPB1 and RPB2 sequences of F. KNU-GC01 matched with those of F. NRRL 13412 (98.3% and 97.6% similarities, respectively); both strains clustered together in the phylogenetic tree, indicating their close relationship at the species level. Therefore, F. is a newly reported pathogen that causes brown spots on apples in Korea.