The images show the leader of the Catholic Church, who is 78, exchanging gifts with the 89-year old Cuban revolutionary after a Mass that drew hundreds of thousands of people in Havana.
Castro and Pope Francis grasp hands and exchange laughs, as shown in images of their private meeting. The pope wears traditional papal garb while Castro wears an Adidas track jacket. The meeting lasted about 30 minutes and included Castro's wife and some of his extended family.
The pope gave Castro a book that the Argentine-born Jesuit wrote. Vatican spokesman Frederico Lombardo described the meeting as a "very informal conversation."
The former president of Cuba is shown giving Francis a book about his thoughts on religion.
The two figures sign each other's books with personal messages. Later, the pope had an official meeting with President Raul Castro, Castro's brother.