HGO

HGO may refer to:
 * HGO Trust (formerly Hampstead Garden Opera), in London
 * Houston Grand Opera, in Houston, Texas, United States
 * Mercury(II) oxide (chemical symbol HgO)
 * Héctor Germán Oesterheld (1919–1977), Argentine science fiction and comics writer, popularly known by his initials HGO
 * Korhogo Airport in Côte d'Ivoire (IATA code HGO)
 * Högskolan på Gotland university of Gotland, Sweden