| Korthio | |
| Name Local: | Κόρθιο |
| Type: | municipal unit |
| Periph: | South Aegean |
| Periphunit: | Andros |
| Pop Municunit: | 1706 |
| Population As Of: | 2021 |
| Area Municunit: | 81.9 |
| Coordinates: | 37.7667°N 80°W |
| Licence: | EM |
Korthio (Greek, Modern (1453-);: Κόρθιο) is a former municipality on the island of Andros, in the Cyclades, Greece. Since the 2011 local government reform it is part of the municipality Andros, of which it is a municipal unit.[1] Its population was 1,706 inhabitants at the 2021 census, and its land area is 81.918 km².[2] It shares the island of Andros with the municipal units of Andros and Ydrousa.