Opisthocentrus is a genus of marine ray-finned fishes belonging to the family Stichaeidae, the pricklebacks or shannies.

Opisthocentrus was first proposed as a monospecific genus in 1868 by the Austrian ichthyologist Rudolf Kner when he described its type species Centronotus quinquemaculatus[1] from "Pinang", although this was probably De Kastri Bay on the Tatar Strait in the northern Sea of Japan.

[5] The largest species is O. ocellatus which has a maximum published total length of 20 cm (7.9 in).

[4] Opisthocentrus fishes are found in the northwestern Pacific Ocean in the waters of Japan, Russia and Korea.

They are demersal fishes living close to the shore in algal beds.