| Athinaio | |
| Name Local: | Αθήναιο |
| Type: | community |
| Coordinates: | 37.4°N 37°W |
| Periph: | Peloponnese |
| Periphunit: | Arcadia |
| Municipality: | Tripoli |
| Municunit: | Valtetsi |
| Pop Community: | 95 |
| Population As Of: | 2021 |
| Licence: | TP |
Athinaio (el|Αθήναιο; before 1928,)[1] is a village and a community in the municipal unit of Valtetsi, Tripoli, Arcadia, Greece. It is situated on a hillside, north of the river Alfeios. The community includes the village Marmaria. Athinaio is 2 km southwest of Asea, 10 km east of Megalopoli and 16 km southwest of Tripoli. The A7 motorway (Corinth–Tripoli–Kalamata) passes south of the village.
| Year | Settlement population | Population community | |
|---|---|---|---|
| 1981 | 294 | - | |
| 1991 | 229 | - | |
| 2001 | 149 | 183 | |
| 2011 | 82 | 95 | |
| 2021 | 85 | 95 |