The two snapshots were released by Prince William and his wife Kate, the Duchess of Cambridge, documenting the early days of Britain’s newest prince.
One of the pictures shows him being held by his sister Princess Charlotte, aged three.
Louis, who is fifth in line to the British throne, was born on 23 April. Due to a 2013 change in the law, Charlotte is the first British princess for whom arrival of a younger brother does not mean being demoted down the line of succession.
The photos were taken by Kate at their home in Kensington Palace.
A palace statement said on Sunday that William and the Duchess are “very pleased” to share the photos.
It is said the royal couple want to thank the public for “all of the kind messages” received since Louis’ birth.