The 94-year-old anti-apartheid hero and Nobel Peace laureate has been treated for a lung infection and gallstones after being hospitalised on December 8.
President Jacob Zuma said in a statement that Mandela "will recover from this episode with all our support... We also humbly invite all freedom loving people around the world to pray for him."
It will be the first Christmas that Mandela has spent away from home since 1989, when he was still in prison. He was jailed for almost three decades for his role in the struggle against white minority rule.
He was released in 1990 and went on to use his prestige to push for reconciliation between whites and blacks as the bedrock of the post-apartheid "Rainbow Nation".
Mandela was elected South Africa's first black president in 1994. He stepped down five years later after one term in office and has been largely removed from public life for the last decade.