The photos were taken by Kate and the royal family-of-five's home in Norfolk.
In the first two photos, presented at the top of the article and below this sentence, pieces of leaves and branches cling from Louis' red sweater.
Few images of the youngest prince were made public.
One fan noted what a great photographer Middleton is, tweeting: "Why is no one talking about Kate being an amateur photographer?"
In this undated handout image released by the Duchess of Cambridge, Prince Louis taken by his mother, the Duchess of Cambridge, at their home in Norfolk earlier this month, to mark his first birthday.
In the pictures, we get to see Prince Louis at his playful best.
The name Louis was already one of George's middle names and pays tribute to the Prince of Wales's great-uncle, Earl Mountbatten, who was murdered by the IRA.
Three new photos of the UK's Prince Louis have been released by his parents, Prince William and Catherine, Duchess of Cambridge, ahead of his first birthday on Tuesday.