Ferox trout (Salmo ferox) is a variety of trout found in oligotrophic lakes/lochs of Ireland, England, Scotland and Wales.

Ferox trout is a traditional name for large, piscivorous trout, which in Scotland feed largely on Arctic char.

It has been argued to be a distinct species, being reproductively isolated from "normal" brown trout (Salmo trutta) of the same lakes, particularly in Ireland.

[1] However, it is uncertain whether the ferox of different lakes are all of a single origin.

[1] This fish grows to a length of 80 centimetres (31 in) SL.