Petalidi is a village and a former municipality in Messenia, Peloponnese, Greece. Since the 2011 local government reform it is part of the municipality Messini, of which it is a municipal unit. Petalidi is situated on the western shore of the Messenian Gulf, 13 km southwest of Messini, 18 km southwest of Kalamata and 21 km east of Pylos. The road Greek National Road 82 (Pylos - Kalamata) passes through the north of the municipal unit.