The former president and anti-apartheid leader returned to his home in Johannesburg, a spokesman said.
The 94-year-old was admitted for tests on Saturday. The checkup was a scheduled appointment and doctors say there's no cause for alarm.
Back in December, Mandela was hospitalized for nearly three weeks for a lung infection. He also had a surgical procedure to remove gallstones.
Under South Africa's white-minority apartheid regime, Mandela spent 27 years in prison before he was released in 1990. He became the nation's first democratically elected president in 1994 under the banner of the African National Congress. He served one five-year term before retiring.
The Associated Press contributed to this report.