| Pierioi | |
| Name Local: | Πιέριοι |
| Type: | municipal unit |
| Periph: | Central Macedonia |
| Periphunit: | Pieria |
| Municipality: | Katerini |
| Population: | 1656 |
| Area: | 112.943 |
| Population As Of: | 2021 |
| Coordinates: | 40.2833°N 39°W |
| Postal Code: | 601 50 |
| Area Code: | +30-2351 |
| Licence: | KN |
Pierioi (Greek, Modern (1453-);: Πιέριοι) is a former municipality in Pieria, Greece. The seat of the municipality was in Ritini. Since the 2011 local government reform it is part of the municipality Katerini, of which it is a municipal unit.[1] The 2021 census recorded 1,656 residents in the municipal unit. The municipal unit has an area of 112.943 km2.[2]