The composition and diversity of microbial communities on plant surfaces and their relationships with plant hosts and the environment have long been of interest. In this paper, we review the latest research results on the composition and diversity of floral microbial communities, spatiotemporal patterns of floral microbial communities, and their interactions with plant hosts and pollinators. Current unresolved problems and future research paths and directions are also discussed. The determinants of floral microbial colonization using a combination of molecular biology and bioinformatics are explored. Furthermore, the spatiotemporal patterns of the floral microbial community are explained in detail. Finally, mutualism between floral microbial community composition and host plants is briefly discussed, which may provide a useful reference for research in the future.