Members of her famous family immediately took to social media to share their excitement. Jackson's sister La Toya Jackson tweeted: "How exciting! Jan and Wissam just gave birth to a beautiful baby boy!!! Congratulations!!!"
Her father Joe Jackson also posted a message saying: "Congratulations Janet!"
A rep for Jackson tells ABC News the pop icon and her husband are thrilled to welcome their new son Eissa. They added that Jackson had a stress-free, healthy delivery and is resting comfortably.
"Sources say she could not be more thrilled right now to be finally expanding her family," said Melody Chiu a staff editor at People Magazine.
The new mom kept a very low profile for much of her pregnancy. She released a baby bump photo exclusively to People Magazine back in October.
At 50, Jackson now joins other super-star moms who decided to have babies later in life, including Kelly Preston who had a son at 48 and Halle Berry who had a baby at 47.