The Victoria's Secret model, 31, and fiancé Jamie Mazur welcomed their new son, Noah Phoenix, in Florianopolis, Brazil on Monday.
The baby boy is the second child for the couple, who have a 3-year-old daughter, Anja. The proud parents took to social media outlets to express their excitement.
Ambrosio gushed on Facebook: "Well, the day just arrived and we couldn't be more happy!!! Noah Phoenix was born yesterday afternoon and already stole our hearts."
Meanwhile, Mazur wrote on Twitter: "Welcome my son, can't wait to show you around this crazy place."
But there's no rest for the genetically blessed - although she just gave birth, the Brazilian beauty already has post-pregnancy jobs lined up, including the launch of the Victoria's Secret store in London in July.She told recently told Vogue: "I already have jobs planned for afterwards so hopefully will be back in shape! I told my booker and my manager, 'I know I have a job to do, so just book the jobs and hopefully it'll be fine.'"