EUSO or Euso may refer to:
EUSO mission, a mission of the European Space Agency EUSO, European Union Science Olympiad, a team-based youth science competition, renamed to European Olympiad of Experimental Science (EOES) in 2021 Euso (spider), a genus of spiders in the family Ochyroceratidae Euso, an old Gascon name for the French town of Eauze
See also USO (disambiguation) EUSOILS, the European Soil Database