In 1979 54 water samples were collected at two oceanographic stations located in Admiralty Bay. Ranges of seasonal changes were found for the values of ten parameters: water temperature, salinity, dissolved О, pH, the contents of PO4 , Si, NO2, NO3, chlorophyll α and plant carotenoids at six depths between surface and 400 m. Data for temperature and salinity showed the absence of distinct thermoclines or haloelines which reflects the very low stability of waters in the Bay. The concentrations of nutrients were high during the entire year and they were not limiting for phytoplankton growth. Only nitrates decreased distinctly during algal blooms. The high dynamics of waters in the Bay causes a lowering in the chlorophyll α content to a maximum of about 2 mg/m3. Oceanographic, hydrochemical and hydrological conditions in Admiralty Bay are typical for the Antarctic shelf waters in this geographical region.