Actress Mila, 31, gave birth to Wyatt in Los Angeles on Tuesday (30 September) and 36-year-old Ashton announced their latest bit of news on his aplus website last night.
However, stressing that the couple are keen to keep Wyatt out of the public spotlight, Ashton tricked fans by posting pictures of FIVE different newborn babies on the site.
In fact, he also threw in snapshots of a dog and a lemur for good measure!
Ashton wrote: "Mila and I would like to welcome Wyatt Isabelle Kutcher to the world.
"May your life be filled with wonder, love, laughter, health, happiness, curiosity, and privacy.
"Can you guess which one is ours, or does it really matter? All babies are cute."
Clearly Ashton's Punked days aren't quite behind him yet!
Mila and Ashton first got together in 2011, although they have known each other since working on That 70s Show in the 90s.
Ashton was preciously married to fellow Hollywood star Demi Moore, however they split after six years together.
In February, Ashton proposed to Mila with a diamond ring and they announced her pregnancy a month later.
Celebrities who have welcomed babies in 2014:
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