The Dream of Gerontius is an 1865 poem written by John Henry Newman consisting of the prayer of a dying man, and angelic and demonic responses. The poem, written after Newman's conversion from Anglicanism to Roman Catholicism, explores his new Catholic-held beliefs of the journey from death through Purgatory, thence to Paradise, and to God. The poem follows the main character as he nears death and then reawakens as a soul, preparing for judgment, following one of the most important events any human can experience: death.

Newman uses the death and judgement of Gerontius as a prism through which the reader is drawn to contemplation of their own fear of death and sense of unworthiness before God. His depiction of the overwhelmed Gerontius in Phase Seven of the poem, who begs to be taken for purgatorial cleansing rather than diminish the perfection of God and his courts of Saints and Angels by his continued presence, has become a popular expression of humanity's desire for healing through redemptive suffering. This scene of the poem has done much for the rehabilitation of the doctrine of purgatory which had previously come to be seen as a fearful terror rather than a state of final purification essentially positive in nature.

Newman said that the poem "was written by accident – and it was published by accident". He wrote it up in fair copy from fifty-two scraps of paper between 17 January and 7 February 1865 and published it in May and June of the same year, in two parts in the Jesuit periodical The Month. The poem inspired a choral work of the same name by Edward Elgar in 1900.

Gerontius owes much of its imagery to the Divine Comedy of Dante Alighieri, an allegorical depiction of travelling through the realms of the dead.