SummaryEndometritis in donkeys is increasingly being recognised in China because of its impact on reproductive performance. Histopathological examination of the endometrial biopsy is the gold standard method for equine endometritis diagnosis, but so far, its application to diagnose donkey endometritis has been limited. In this study, 48 jennies at donkey farms in Hebei province, China, diagnosed with endometritis had an endometrial biopsy performed from 2019 to 2021 for histopathological examination and were categorised into grade I (2/48), IIA (24/48), IIB (15/48) and III (7/48). Selected typical endometrial biopsy samples of each category along with cytology from four jennies with endometritis were described more specifically.