Microbiology is still full of secrets and honey seems to be the indicator of bee state. This book is about primary sources of microorganisms in the honey; microbial quality of honey; correlations between the physico-chemical properties and microbial parameters in honey; occurrence of Paenibacillus larvae and microbial dynamics in honey blended with pollen during storage. Microbial groups and counts differed in the honey compared with related materials (pollen and honeybees). Penicillia were the dominant genus of microscopic filamentous fungi found in honey. The highest absolute correlation coefficient value between the values of the physico-chemical properties on one hand and the values of microbial parameters on the other was 0.40. Bacterial isolates originating from a brood comb with clinical symptoms of American foulbrood were identified as Paenibacillus larvae by biochemical and molecular genetics methods. Fermentation in the honey blended with pollen was observed after four months of storage at room temperature. The water content in the original honey sample was a critical factor. The result of this study will be of use in the field of research and in beekeeping.