The paper considers the thermohaline structure of Black Sea abyssal and near-bottom waters on the basis of exact measurements recorded in recent years under the HYDROBLACK and COMSBLACK international projects. The surface water mass, the intermediate, abyssal, and near-bottom masses are identified. The upper boundary of deep waters is defined as a depth level where the density ratio decreases down to 0.1. This depth roughly corresponds to the 900-1100 m depth levels. Furthermore, the paper provides potential temperature and salinity values in the near-bottom layer, with an error of, respectively, 0.002°C and 0.002‰, at most.