Eudocia, or Eudoxia (439 – 466/474?) was the eldest daughter of Roman emperor Valentinian III and his wife, Licinia Eudoxia. She was thus the granddaughter on her mother's side of Eastern emperor Theodosius II and his wife, the poet Aelia Eudocia; and on her father's side of Western emperor Constantius III and his wife Galla Placida.
In the mid-440s, at age 5, Eudocia was betrothed to Huneric, son of the Vandal king Gaiseric (and then a hostage in Italy). This engagement served to strengthen the alliance between the Western court and the Vandal kingdom in Africa. Their marriage did not take place at this time, however, because Eudocia was not yet of age.
Eudocia's father was assassinated in 455, and his successor, Petronius Maximus, compelled Eudocia's mother to marry him and Eudocia herself to marry his son, Palladius. In response, the Vandals (reportedly at the request of Eudocia's mother) invaded Italy and captured Eudocia, her mother, and her younger sister, Placidia. After 7 years Eudocia's mother and sister were sent to Constantinople, while Eudocia remained in Africa and married Huneric c. 460. They had a son, Hilderic, who reigned as king of the Vandals, from 523-530.
At some time following the birth of Hilderic, Eudocia withdrew to Jerusalem due to religious differences with her Arian husband. She died there and was buried in the sepulcher of her grandmother, Aelia Eudocia.