Jolie, whose thin frame was covered by black leather trousers and a tight sweater, signed autographs and chatted with some of the hundreds of fans outside the theatre.
It's so, so nice to see all these fans here, it always is," she told reporters.
"I haven't been here for a little bit. I lived here for a few years, and I do plan to come back more often."
Jolie appeared relaxed and happy, despite getting one of her black Christian Louboutin stilleto heels stuck in chewing gum on the red carpet.
Pitt, dressed in a grey flat-cap, refused to steal the limelight, telling reporters "I'm off duty tonight."
Beowulf co-stars Sir Anthony Hopkins and Ray Winstone also showed up for the premiere.