The former couple were married from 2000 to 2005, before Brad got together with Angelina Jolie, who he eventually married in 2014.
They were photographed together backstage at the ceremony after Brad won the Best Supporting Actor award for Once Upon A Time… In Hollywood and Jennifer was recognised with the Outstanding Performance By A Female Actor In A Drama Series for The Morning Show.
Photos taken backstage at the event in LA show them with beaming smiles after running into each other.
If that wasn’t enough, a video of Brad attentively watching Jen collect her prize has also surfaced.
Earlier in the evening, Brad - who split from Angelina in 2016 - made a joke about his colourful love life as he picked up his prize for the Quentin Tarantino film.
“It was a difficult part, a guy who takes his shirt off, gets high and doesn’t get on with his wife. It was a big stretch, big,” he joked.
At the Golden Globes earlier this month, Brad was reminded that the world is still as interested in his personal life as his efforts on the big screen.
Entertainment Tonight reporter Kevin Frazier suggested “the world, the internet” was “hoping for this moment where you and Jennifer run into each other, so [they] can take [your] picture”.
Brad was unfazed by the question, referring to his ex-wife as his “good friend” who he was sure he’d “run into” over the course of the evening.
“The second most important reunion of her year? I understand,” Brad added, referring to the much-rumoured Friends reunion.