Alfonso II (4 November 1448 – 18 December 1495) was Duke of Calabria and ruled as King of Naples from 25 January 1494 to 23 January 1495. He was a soldier and a patron of Renaissance architecture and the arts.

Heir to his father Ferdinand I's Kingdom of Naples, Alfonso held the dukedom of Calabria for most of his life. In the 1480s Alfonso commanded the Neapolitan forces in Tuscany in 1478–79. He helped reverse the Ottoman invasion of Otranto in Apulia in 1480–81, and against the Republic of Venice in 1484. In 1486 Alfonso's repressive conduct towards the Neapolitan nobility prompted a revolt; the violent excesses of suppressing this uprising further discredited Alfonso and King Ferdinand. Under Alfonso's patronage the city of Naples was remodelled with new churches, straightened roads, and an aqueduct supplying fountains.Alfonso became King of Naples in 1494 on his father's death. Within a year he was forced by the approaching army of Charles VIII of France to abdicate; he was succeeded by his son Ferdinand II of Naples. Alfonso went into an Olivetan monastery at Mazara del Vallo, on Sicily, where he survived until 18 December 1495.