San Fratello (Gallo-Italic: San Frareau, Sicilian: Santu Frateddu, Greek and Latin: Apollonia,[3] Medieval Latin Castrum S. Philadelphi), formerly San Filadelfo, is a comune (municipality) in the Metropolitan City of Messina in the Italian region Sicily, located about 110 kilometres (68 mi) east of Palermo and about 90 kilometres (56 mi) west of Messina.

In the following decade, it lost nearly 20 percent of its population, as people migrated for work to cities and to other countries, especially the United States.

The village was founded in the 11th century by Adelaide del Vasto, the wife of Roger I, a noble of present-day French Normandy who conquered Sicily.

San Fratello is one of the so-called Oppida Lombardorum of Sicily, settlements established by the Lombards.

On 1–2 October 2009, the province of Messina suffered devastating, widespread mudslides after a sudden heavy rainstorm; scores of residents died.