The baby was delivered at 16:24 BST at St Mary's Hospital in Paddington, west London, weighing 8lb 6oz.
The palace said in a statement that the duchess and the baby
were "doing well". She and Prince William will remain in the hospital
The news has been displayed on an easel in the forecourt of Buckingham Palace in line with tradition.
Read about 10 curious things about the royal birth. Click HERE