The analysis of net catches made in Absheron Gulfs of the Caspian Sea during 2011-2012 is provided. The ichthyofauna of Absheron Gulfs, including 26 species found in the North Gulf, and 33 species and subspecies found in the South Gulf was studied for the first time. A taxonomical and ecological diversity of the fish fauna of North and South Absheron Gulfs is characterized. The peculiarities of distribution and population densities of all species of fishes from different families within the studied territories were analyzed. For each of hydrological seasons, numerous, common, infrequent and rare species were revealed. On migration patterns and catch, the lowest biomass of fishes was observed in the warm season, while the highest was in the winter and spring seasons. The tendency of expansion of ranges of some marine fishes-Gasankuli herring Alosa braschnikowi kisselewitschi, Sara herring A. braschnikowi sarensis, big-eyed herring A. braschnikowi autumnalis, Sara shad A.caspia knipowitschi- to the north was recorded.