Alfonso II (Aragon) or Alfons I (Provence and Barcelona); Huesca, 1–25 March 1157 – 25 April 1196), called the Chaste or the Troubadour, is the King of Aragon and Count of Barcelona from 1164 until his death.

He is the son of the count Ramon Berenguer IV of Barcelona and the Queen Petronilla of Aragon and the first King of Aragon who is also Count of Barcelona.

He is also Count of Provence from 1166 or shortly before which he acquires from Countess Douce II, until 1173, when he cedes it to his brother Berenguer.

His reign has been characterized by nationalistic and nostalgic Catalan historians, as l'engrandiment occitànic or "the Pyreneean unity": a great scheme to unite various lands on both sides of the Pyrenees under the rule of the House of Barcelona.