Julia Iotapa or Julia Iotape (born c. 45), daughter of King Antiochus IV of Commagene, was a Queen of Cetis, consort of Gaius Julius Alexander, son of Herodian prince Gaius Julius Tigranes.
Iotapa's eldest brothers were princes Gaius Julius Archelaus Antiochus Epiphanes and Callinicus.
Iotapa's father Antiochus IV was an ally to the Roman Emperor Nero and various members of the Herodian Dynasty.
The majority of Armenians had abandoned resistance and wanted peace, which included accepting a prince to be crowned by Nero as the king of Armenia.
After the marriage of Iotapa and Alexander occurred in Rome, Nero crowned them Queen and King of Cetis, a small region in Cilicia, that was previously ruled by her father.