John XIX, né Romanus (died October 1032) was pope from 1024 to 1032.

He succeeded his brother Benedict VIII, both being members of the powerful house of Tusculum. When elected pope he was an unordained layman. Therefore, he was ordained a bishop in order to enable him to ascend the papal chair, having previously been a consul and senator.

He displayed his freedom from ecclesiastical prejudices, if also his utter ignorance of ecclesiastical history, by agreeing, on the payment of a large bribe to grant to the Patriarch of Constantinople the title of an ecumenical bishop, but the general indignation which the proposal excited throughout the church compelled him almost immediately to withdraw from his agreement.

On the death of the emperor Henry II in 1024 he gave his support to Conrad II, who along with his consort was crowned with great pomp at St Peter's on Easter of 1027.

After John's death, his nephew Benedict IX was found as a successor, although he was still young: according to some sources, he was only 12, but he was more likely to have been about 18 or 20.

Note that the next pope named John was Pope John XXI and there is no Pope John XX (see article for explanation).