The huchen /ˈhuːkən/ or Danube salmon (Hucho hucho) is a large species of freshwater fish in the salmon family of order Salmoniformes. It is the type species of its genus. The huchen is endemic to the Danube basin in Europe where the remaining population is threatened by overfishing and habitat loss. It has been introduced elsewhere on the continent and in Morocco, but most of these populations are not self-sustaining. In historic times the huchen has also been found in the Dniestr basin.