Saint Alphius (; ) is a (municipality) in the Metropolitan City of Catania in the Italian region Sicily, about east of Palermo and about north of Catania.
Saint Alphius borders the following municipalities: Adrano, Belpasso, Biancavilla, Bronte, Castiglione di Sicilia, Giarre, Linguaglossa, Maletto, Mascali, Milo, Nicolosi, Piedimonte Etneo, Randazzo, Zafferana Etnea.