Liocarcinus navigator is a species of crab in the family Portunidae.

[2] This species is found chiefly around the British Isles; its range covers the north-east Atlantic Ocean, including the North Sea as far north as Trøndelag in Norway, and as far south as Mauritania, and it also occurs in the Mediterranean Sea.

[3][4] Liocarcinus navigator has a dark brown carapace up to approximately 33 millimetres (1.3 in) wide,[3] with lighter pereiopods.

[5] The frontal margin of the carapace, between the eyes, has a fringe of hair but no spines.

[3][5] Two subspecies are recognised:[1]