"Her Royal Highness The Duchess of Cambridge will be discharged this evening from St Mary's Hospital, Paddington," the palace said.
"The Duke and Duchess of Cambridge and their son will travel home to Kensington Palace."
The statement said that William and Kate wanted to "reiterate their thanks to the hospital for the care and treatment they have all received".
Britain was in full celebratory mood today after Prince William's wife Kate Middleton gave birth to a bouncing baby boy - the third in line to the throne - with hundreds thronging the street leading to the hospital.
The Duchess of Cambridge, 31, gave birth yesterday to the baby boy, weighing 3.8 kilos (8 lbs 6 oz), at the private Lindo wing at St Mary's Hospital in Paddington here.