Suecoceras is an endoceratid (a kind of nautiloid cephalopod) that lived during the Middle Ordovician. It is characterised by a long, straight, slender shell with a slightly expanded tip that curves slightly downwards. The siphuncle takes up the entire apex, but is not swollen as in Chazyoceras or Nanno. A typical species, S. barrande (Dewitz), whose fossil remains are known from Sweden (hence the name, Sueco- means "Swedish"), has a shell about 15 cm (5.9 in) long.