A comparative study of the surface layer bio-optical properties of the Barents and Norwegian Seas in the summer of 2017 is carried out. Ship data were obtained during the 68th cruise of the R/V ‘Akademik Mstislav Keldysh’ (June-August 2017). Using a flow-through system, the fluorescence intensities of chlorophyll ‘a’ and dissolved organic matter, salinity and temperature of the water surface layer along the ship’s route were continuously recorded. At the sampling stations, the reflectance spectra were measured. Samples were taken for spectral fluorescence and absorbance measurements performed with a laser spectrometer and an integrating cavity absorption meter. The results are compared with the data of direct determinations of the chlorophyll concentration. In the Barents Sea, the results of shipboard measurements are compared with the data of OLCI satellite scanner. Frequent continuous cloudiness prevented the use of ocean color data for the Norwegian Sea. A comparative study of the fluorescence, absorption, and reflectance spectra has shown the possibility of carrying out a rapid assessment of the phytoplankton species composition and its concentration. In particular, these data made it possible to detect the coccolithophore bloom in the Barents Sea. The change in the coefficients of the regression equation of chlorophyll fluorescence intensity and its concentration, determined by direct methods for different regions, is shown.