In this paper microscopic analyses of a honey sample from Black Sea Region of Turkey was done to deter- mine its botanical origin. According to the results of microscopic analysis, the honey sample is evaluated as chesnut honey. Besides this an unexpected contaminant was observed in this honey sample. As well as pollen grains, Ustilago spores are also identified in the sample in quitely high values during the microscopic analysis. Members of Ustilago genus are plant pathogen fungus. Therefore, it is considered that these spores can be transported to the hive by honey bees while they are collecting pollen or nectar. Ustilago spores are reported as an allergen associated with bronchial asthma and with hypersensitivity pneumonitis. In the honey, amount of observed spores were found higher than pollen grains’ and it is predicted that this honey could be hazardous to health. Consequently, our research exhibited the importance of microscopic analysis for honey quality and hygiene control.