Urothoe marina is a species of small marine amphipod crustaceans in the family Urothoidae.

It is found on and burrowing in coarse sediments in shallow coastal waters off northwestern Europe.

Its range includes the North Sea, the English Channel and the Atlantic Ocean from the Shetland Isles southwards to the Bay of Biscay.

[4] The back three legs of U. marina have flattened joints and are used for digging and it can quickly disappear into the substrate.

[2] It is often found in association with the sea potato (Echinocardium cordatum), making use of its burrow as a refuge.