Frederick II (or III) (13 December 1272 – 25 June 1337) wis the regent (from 1291) and subsequently King of Sicily from 1295 until his death.

He is the third son of Peter III of Aragon and serves in the War of the Sicilian Vespers on behalf of his father and brothers, Alfonso and James.

He is confirmed as King of Trinacria (another name for the island of Sicily) by the Peace of Caltabellotta in 1302.

His reign saees important constitutional reforms: the Constitutiones regales, Capitula alia, and Ordinationes generales.