This report presents preliminary results from a seabed mapping and biodiversity survey of Beagle Marine Park, undertaken in 2018 by the University of Tasmania, Geoscience Australia and University of Sydney Centre for Field Robotics. The primary audience includes researchers and marine park managers. Bathymetry mapping and seabed imagery reveals the area is dominated by soft sediments, with localised areas of low-profile reef, including rare examples of relict terrestrial dunes that formed when Bass Strait was a land bridge. The reefs provide important habitat for sessile invertebrates, while adjacent soft sediment areas include scallop beds interspersed among coarse sand, with shell fragments and extensive fields of sediment bedforms. Demersal fish were abundant and diverse, but with few commercial or recreational target species. These new data provide insights into the distribution of seabed habitats and biota within Beagle Marine Park, and provides a baseline on its natural values.