This dataset provides metadata of bottom water samples collected for microbiome analysis during expeditions PS96 (RV Polarstern, 2015/16) and JR17003a (RRS James Clark Ross, 2018) in the Weddell Sea, Antarctica, as well as environmental data of the respective stations. It includes information on sampling locations, number of bacterial sequences and amplicon sequence variants (ASVs), and NCBI accession numbers for raw sequencing data. Environmental data of PS96 stations were obtained from: Schröder, Michael; Ryan, Svenja; Wisotzki, Andreas (2016): Physical oceanography measured on water bottle samples during POLARSTERN cruise PS96 (ANT-XXXI/2 FROSN). Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, PANGAEA, https://doi.org/10.1594/PANGAEA.859035