| Castello di Annone | |
| Official Name: | Comune di Castello di Annone |
| Coordinates: | 44.8833°N 27°W |
| Region: | Piedmont |
| Province: | Asti (AT) |
| Frazioni: | Alberoni, Bordoni, Crocetta, Monfallito, Poggio |
| Mayor: | Valter Valfrè |
| Area Total Km2: | 23.2 |
| Population Total: | 1963 |
| Population As Of: | 1 January 2010[1] |
| Population Demonym: | Annonesi |
| Postal Code: | 14034 |
| Area Code: | 0141 |
Castello di Annone is a comune (municipality) in the Province of Asti in the Italian region Piedmont, located about 50km (30miles) southeast of Turin and about 9km (06miles) east of Asti.
Castello di Annone borders the following municipalities: Asti, Cerro Tanaro, Quattordio, Refrancore, Rocca d'Arazzo, and Rocchetta Tanaro. Its name derives from the Latin ad nonum ("nine miles"), indicating its distance from Asti. In the Middle Ages it was an important strategic hub, until it was destroyed by Spanish troops in 1644. In 1994 it was flooded by the nearby Tanaro river.