Eustachius may refer to:

  • Variant of the name Eustathius
  • Saint Eustachius
  • Sint Eustatius, Dutch island in the Caribbean
  • Bartolomeo Eustachi (c. 1500–1510 – 1574), anatomist
  • Eustáquio van Lieshout (1890–1943), Dutch missionary in Brazil
  • Eustachius Kugler, beatified German religious
  • Eustochius, fifth bishop of Tours from 443 to 460
  • Eustathius, son of Macrobius

<!-- Long comment to avoid being listed on short pages -->