The X-Men actress, 47, is said to have given birth to a baby boy in Los Angeles on Saturday (5 Oct).
The baby would be the first child for Halle and husband Olivier, but the second child for Halle who has a five-year-old daughter, Nahla, with ex-fiancé Gabriel Aubry.
E! Online reports that Halle delivered the baby boy at Cedars Sinai Hospital, where celebrities including Kim Kardashian have given birth.
Over recent weeks, Halle has been seen sporting a huge bump as she prepared for the birth of her child.
Halle and Olivier were married in France in July - Halle's third marriage.
The Oscar-winning actress was previously married to baseball player David Justice in the early 90s and to singer Eric Benét in the early 2000s.
Do you think Halle and Olivier make a cute couple? Tell us what you think below!