Taking to Twitter on Wednesday, the Tron Legacy actress wrote: 'Ladies and gentlemen, Otis Alexander Sudeikis has LEFT the building (I'm the building).' The star also included an adorable snap of her and the new baby - who was born almost two weeks early.
Wilde announced her pregnancy in October, nine months after her and We're the Millers actor Jason Sudeikis became engaged.
Both Sudeikis and Wilde have been married before, Sudeikis to actress and writer Kay Cannon for four years, and Wilde to Italian filmmaker and musician Tao Ruspoli. Wilde was just 19-years-old when she married the Italian - which she did on a school bus with just two witnesses. After 8 years of marriage, the pair announced that they were seperating.
Otis Alexander is the first child for both Wilde and Sudeikis however, and they are no doubt enjoying every second of their newborn today.
Congratulations to the happy couple!