Odell Beckham Jr. is rallying behind Chris Brown, who’s been sitting in a UK jail cell since Thursday, taking to social media with a message of support — “Free Breeeezyyy!”

Brown, 36, was locked up last week for an alleged incident going back to 2023 … when the Grammy Award-winning performer allegedly smashed a liquor bottle over a music producer’s head.

CB was charged with one count of grievous bodily harm … and will remain in custody until his first appearance at London’s Southwark Crown Court on June 13.

Breezy fans have been outraged over the idea of Chris sitting behind bars … and Beckham is right there with ’em.

Beckham, who last played for the Miami Dolphins, is good buddies with Chris — the guys go back years together — so it’s no surprise OBJ has CB’s back.

As for how the arrest went down, Chris was arrested at Manchester Airport in the UK after flying into the country on a private jet.