Key messageThe datasets describe bacterial and fungal communities of European beech (Fagus sylvatica) leaves collected along a vertical gradient in a gallery forest throughout the growing season. They also describe communities in the surrounding environment of beech trees. Dataset access is at https://doi.org/10.7910/DVN/FFHAQU, and associated metadata are available at https://metadata-afs.nancy.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/f17fe848-fc3e-4297-be11-9871b35a1be4. Both can be used to uncover the dynamics and assembly processes of phyllosphere microbial communities in forest ecosystems.