Neogobius bathybius is a species of goby endemic to the Caspian Sea, where it occurs in depths down to 200 metres (660 ft).

It is strictly confined to the brackish-water basin and does not enter fresh waters.

It can grow up to a length of 25 centimetres (9.8 in) TL.

[1] The species was transferred to the genus Ponticola from Neogobius on the basis of relationship revealed in molecular investigations.

[2] On the other hand, recent molecular studies have proven that this species belongs entirely to the genus Neogobius.