Abstract: Ice-shelf loss along the east coast of the Antarctic Peninsula over recent decades has brought new sources of carbon and energy to the marine benthos likely affecting sediment geochemistry and microbial community composition. To better understand the long-term effects of ice-shelf loss on benthic microbial communities, we conducted a five-station survey along a 160 km transect following the historic path of retreat of the Larsen A ice shelf. All microbial community sequence data is publicly available through the Metagenomics Analysis Server at Argonne National Laboratory (MG-RAST). The project title is "Impact of ice-shelf loss on geochemical profiles and microbial community composition in marine sediments of the Larsen A embayment, Antarctic Peninsula". A key word search using terms from this title at the MG-RAST portal (http://metagenomics.anl.gov/) will return the complete sample list. This submitted dataset summarizes the measured environmental parameters for these same samples (lat., long., water depth, sediment depth, pH, alkalinity, dissolved oxygen, silicate, phosphate, nitrate, nitrite, and ammonium).