Thandie, 41, posted the picture on her Twitter page, with the caption, "Happy holidays."
The star and her husband OI Parker welcomed their third child together on 3 March. Proudly announcing his arrival, Thandie posted, "Our baby boy is finally here! Booker Jombe Parker. Born joyously at home yesterday."
It was the third time that Thandie has successfully delivered her baby at home, and she also thanked her child birth assistants Phoenix Midwives.
"My 3rd home birth with brilliant independent midwife Caroline Flint — and Carole Goddard @PhoenixMidwives," she wrote. "Keep independent midwifery alive!"
Thandie and her husband, who have been married since 1998, are also proud parents to daughters Ripley, 13, and Nico, nine.
Happy Holidays pic.twitter.com/yRa8ik9JAP— Thandie Newton (@thandienewton) April 15, 2014
OI also announced the arrival of his son on Twitter, writing, "We had a baby, that's a beautiful thing. He's called Booker, and while he doesn't do much yet, I suspect him to be awesome.
"Many thanks for all the new baby wishes I haven't replied to personally. For taking the time, and sending the love; both much appreciated."