Omonoia may refer to:
- Omonoia Square, one of Athens' main squares, Omonoia Station, the subway station located on the square or Omonoia, the neighborhood around it.
- Omonoia (organization), a political and cultural organization of the Greeks living in Albania
- AC Omonia, a Cypriot football/soccer team
Omonoia is a Greek social, political and cultural organization in Albania that promotes minority rights for the Greek minority in the south of the country.