The 'Run the World (Girls)' singer arrived at the MTV Video Music Awards (VMAs) last night (28.08.11) in a loose fitting orange dress, and clutched her visible baby bump as she posed on the red carpet.
She told the press: "I have a surprise!"
Beyonce's publicist later confirmed the news, telling People.com: "I'm happy to say it's true."
The child will be the first for the 29-year-old and her husband, rapper Jay-Z, who married in 2008.
During the VMAs Beyonce first cheered on Jay from the side of the stage as he performed new single 'Otis' with Kanye West, then wowed the Nokia Theatre in Los Angeles herself, singing 'Love on Top'.
She told the crowd: "I want you to feel the love that's growing inside of me."
As she sung, Beyonce proudly rubbed her bump, and the cameras panned over to Jay-Z, who had a huge grin on his face. The performance was met with a standing ovation.
Beyonce has recently hinted she was thinking of settling down, saying earlier this month how she was hoping to "dedicate herself" to having children.
She said: "When you're young - 18 or 19 - you have the energy and drive. That's the time to work as hard as you can.
"Now I'm a woman, and because I gave it my all, I can focus on my marriage. I can decide I want to have kids. I can be the mother I want to be and dedicate myself to my children."
The cameras panned to the audience where Jay-Z was beaming, as his friend Kanye jumped up and down, smacking the father-to-be on the back.
The singer didn’t let her pregnancy prevent her from bringing the house down with an energetic performance.
Speaking to Piers Morgan in June, she hinted: ‘I always said I was going to have a baby at 30. I’m 29 now.