The CTD data on cruise M164 contain oceanic measurements of temperature, salinity, oxygen and pressure at 126 stations. The data were collected with the research vessel Meteor during cruise M164: Region: subpolar North Atlantic, 9°W-47°W, 45°N-53°N; Ports: Emden - Emden; Date: June 23 - July 31, 2020 . The data where collected by a CTD device of type SBE 9. The CTD was mounted to a metal frame with 22 water sample bottles, which was lowered from the sea surface down to 10 m above the seafloor. The sampling frequency was 24 Hz, the raw data were then interpolated on 1 dbar intervals. Salinity and oxygen data from the CTD were calibrated by comparison with samples from the water bottles. The bottle salinity was analysed by a salinometer of type Guildline Autosal 8400A, bottle oxygen samples by Winkler titration. The accuracy of the calibrated CTD measurements is: 1 dbar for pressure, 0.001 °C for temperature, 0.0025 for salinity, 3.0 µmol/kg for oxygen. Detailed information can be found in the cruise report: https://doi.org/10.48433/cr_m164.