Deo may refer to:
- Deo, a synonym of the Greek goddess Demeter.
- Deo, Central African Republic
- Western Economic Diversification Canada, (French: Diversification de l'économie de l'Ouest Canada), a Canadian government agency
- Deutsche Evangelische Oberschule, a German school in Cairo, Egypt.
- Deo/Dewu/Deu, a boss in the MMORPG Maplestory.