Three oceanographic cruises were organized in the seas around Sardinia (western Mediterranean) between September 2019 and September 2021 (see the table) by the Italian National Research Council (CNR) and the acquisition of 241 hydrological vertical profiles by a SBE 911plus V 5.1g. Data of conductivity (SBE-4 sensor, resolution of 3 x 10-4 S/m), temperature (SBE-3/F thermometer, resolution of 0.00015 °C/bit at -1 °C or 0.00018 °C/bit at 31 °C), dissolved oxygen (DO; SBE-43 polarographic membrane sensor with a range of 120% of surface saturation and an accuracy of ±2% of saturation), Chlorophyll-a fluorescence (Chl-a; Chelsea Aqua 3 Con in ug/l) reported as Relative Fluorescence Unit. Turbidity was acquired by a WET Labs ECO-NTU. The pH/Redox sensor (SBE27) was available just during the cruise IDMAR2019. Data were quality checked and processed by the Sea-Bird Seasoft© software, and the coarse errors corrected. In all three cruises the 35-meter-long R/V G. Dallaporta was used. The data set is provided per cruise as Ocean Data View (ODV, Schlitzer, 2024) Spreadsheet files in TXT format where missing data values are set to -1.e10. The cruises have been realized in the framework of the project Distributed Research Infrastructure in the Sea (IDMAR) funded by the Italian National Research Council and the Regional Operational Programme “Sicily 2014-2020” in the framework of the European Regional Development Fund (ERDF). DataVariable Pressure, Digiquartz [db] Temperature [deg C]; ITS-90 in all other cruises Conductivity [mS/cm] Oxygen, SBE43 [ml/l] in all cruises Oxygen, SBE43 [% saturation] Fluorescence, Chelsea Aqua 3 Chl Con [ug/l] in all cruises pH/Redox, SBE27 just in IDMAR2019 Turbidity, WET Labs ECO [NTU] in all cruises Table : List of cruises organized in the period 2019-2021 with the number of casts per cruise, the areas interested and the dates of the calibration of sensors before each cruise (month and year)