Chalkbrood is a fungal disease of honey bees and leads to serious apicultural loss worldwide. Ascosphaera apis, the pathogen of chalkbrood, has been found in Apis mellifera, Apis cerana, Xylocopa californica arizonensis larvae as well as adult bumble bees. Here, the fungal pathogen of Apis cerana cerana drone mummies was isolated and identified using morphological and molecular methods. Morphological observation indicated that the sizes of the fruiting bodies, spore balls and ascospores of the fungus isolated from A. c. cerana drone mummies were similar to those of A. apis. Phylogenetic analysis suggested that the fungus is identical to A. apis. Furthermore, the results of a cross infection assay demonstrated that the isolated fungus is capable of infecting eastern and western honey bee larvae and results in chalkbrood. These results confirmed that the isolated fungal pathogen is A. apis. This is the first documentation of morphological and molecular identification of A. apis in A. c. cerana. Our results not only provide novel insight to better understand the pathology of A. apis, but also lay a solid foundation for further investigations of host responses and pathogen-host interactions during chalkbrood of eastern honey bee larvae.