| Posta Fibreno | |
| Official Name: | Comune di Posta Fibreno |
| Coordinates: | 41.7°N 55°W |
| Region: | Lazio |
| Province: | Frosinone (FR) |
| Mayor: | Adamo Pantano |
| Area Total Km2: | 9.8 |
| Population Footnotes: | [1] |
| Population Total: | 1104 |
| Population As Of: | 31 July 2017 |
| Population Demonym: | Postesi |
| Elevation M: | 430 |
| Postal Code: | 03030 |
| Area Code: | 0776 |
Posta Fibreno (locally Italian: La Posta) is a comune (municipality) in the Province of Frosinone in the Italian region Lazio, located about 100km (100miles) east of Rome and about 30km (20miles) east of Frosinone. Posta Fibreno borders the following municipalities: Alvito, Broccostella, Campoli Appennino, Fontechiari, Vicalvi.
In 1927, following the reorganization of provincial circumscriptions established by royal decree no. 1 January 2, 1927, by the will of the fascist government, when the province of Frosinone was established, Posta Fibreno, as a locality of Vicalvi, passed from Caserta province to that of Frosinone. In 1957, with the law of 5 March 1957 n. 91, left the territory of Vicalvi.