This data set named the Kongsfjorden Transect data is a subset of the UNIS Hydrographic Database (UNIS HD). UNIS HD is a collection of temperature and salinity profiles from the area (1-30°E and 75-81.5°N). The main portion of the Kongsfjorden Transect data were collected during the period 1994-2014 by The University Centre in Svalbard (UNIS), University of Bergen (UiB), Norwegian Polar Institute (NPI), Institute of Oceanology Polish Academy of Sciences (IOPAS) and the Arctic University of Norway (UiT). Additional data in the database have been extracted from other data publishers; the Norwegian Marine Data Centre (NMDC, https://www.nmdc.no/), the International Council for the Exploration of the Sea (ICES) conductivity, temperature and depth (CTD) database ( https://ocean.ices.dk/HydChem/), the PANGAEA data publisher ( https://www.pangaea.de/), and the database from the project Norwegian Iceland Seas Experiment (NISE; Nilsen et al., 2008).