An entomophthoraceous fungus, Zoophthora phalloides, was found in populations of the aphid Dactynotus species, at National Institute of Agricultural Science and Technology, and Jeonnam Provincial RDA during June, 1998. Occurrence of the fungus and aphid has never been recorded in Korea. Microscopic observations of this fungus are described, and illustrated. The fungus has sausage-shaped primary conidia with $28.98;{mu}m$ in length, and two types of secondary conidiophores. Our specimens exhibit closer relationship with the North American isolates than with the European isolates on the basis of conidial length described by other study.