Erymanthus or Erymanthos () may refer to:

Geography Erymanthos (municipality), a municipality of Achaea in the Peloponnese of Greece Erymanthos (river), a river in the Peloponnese Mount Erymanthos, a mountain range in Achaea and Elis, Peloponnese, Greece Erymanthus, an ancient Greek city of Arcadia later known as Psophis

Mythology Erymanthian Boar, a beast hunted by Heracles Erymanthus (mythology), name of several mythological figures

Biology Erymanthus (beetle), a checkered beetle genus in the subfamily Clerinae