Palaiologos, often latinized as Palaeologus, is a Byzantine Greek noble family that produces the last ruling dynasty of the Byzantine Empire.

After the Fourth Crusade, members of the family fled to the neighboring Empire of Nicaea, where Michael VIII Palaiologos becomes co-emperor in 1259, recaptures Constantinople and is crowned sole emperor of the Byzantine Empire in 1261.

His descendants rule the empire until the Fall of Constantinople at the hands of the Ottoman Turks on May 29, 1453, becoming the longest-lived dynasty in Byzantine history; some continue to be prominent in Ottoman society long afterwards.

A branch of the Palaiologos become the feudal lords of Montferrat, Italy.

This inheritance is eventually incorporated by marriage to the Gonzaga family, rulers of the Duchy of Mantua, who are descendants of the Palaiologoi of Montferrat.