The gobies are non-commercial fishes in the Iranian waters of the Caspian Sea for which population dynamics and stock status are poorly known. In this survey, we tried to define species diversity and catch per unit effort (CPUE) of Gobiidae by using beach seine nets in Salmanshahr, the southern Caspian Sea. From March 2011 to April 2012, 224 specimens representing 4 gobiid species, belonging to genus Ponticola and Neogobius, were caught. The deepwater Goby, Ponticola bathybius (Kessler, 1877), was the most abundant species with 92.8% frequency. The highest catch per unit effort of gobiid fishes was obtained in spring. The species diversity was highest in spring according to Shannon’s index.