This study provides the first molecular characterisation of the bacterial community composition off the coast of Mauritania and Senegal. During the Meteor M129 cruise coastal, shelf and open water samples were taken for 16S Illumina MiSeq sequencing of both particle-attached (PA >3.0 µm) and free-living (FL 0.2-3.0 µm) fraction. Additionally, environmental drivers for a-diversity, bacterial community composition and differences between PA and FL bacteria were identified.