The four-month-old royal made his first appearance of Harry and Meghan's Africa tour by posing with one of the heroes of the anti-Apartheid movement as he was held by his proud parents.
Archie was the centre of attention as the group, which included the archbishop's daughter Thandeka Tutu-Gxashe, joked about his time in front of the cameras.
Meghan said "He's an old soul" while Harry commented: "I think he is used to it already."
The archbishop's daughter also joked: "You like the ladies. He's going to be a ladies man."
The veteran Nobel Peace Prize winner, who was effectively the leader of the liberation struggle during Nelson Mandela's long imprisonment, said he was "thrilled by the "rare privilege and honour" to meet the royals.
The 87-year-old cleric spent half an hour with the couple and Archie at the historic premises of his Legacy Foundation in Cape Town, the Old Granary, a restored centuries old edifice built by slaves.