Giovanni Dolfin (or Delfino) (Venice, 22 April 1617 - Udine, 20 July 1699) was an Italian Catholic Cardinal, writer and playwright, Patriarch of Aquileia from 1657 to his death.

On the request of the Republic of Venice, on 18 July 1667 Pope Alexander VII appointed him Cardinal-Priest of San Salvatore in Lauro and then Cardinal-Deacon of Santi Vito, Modesto e Crescenzia.

He wrote three historical tragedies based on the traditional Counter-Reformation conflict between reason of state and love or personal ethics: Cleopatra, Lucrezia, Creso; and a free adaptation from the Orlando Furioso, Medoro, all printed posthumously.

Delfino appears to be very well versed in the New Science, discusses Pierre Gassendi’s and Galileo’s theories, Lucretius' atomism, the philosophy of Franciscus Patricius and Francis Bacon and the scientific and philosophical ideas of Fortunio Liceti and Athanasius Kircher.

[2] He wrote also poems on celebratory, heroic or meditative subjects and ethical and political remarks on Sallust's Bellum Catilinae and Tacitus's Agricola.