The Migos rapper surprised the crowd - and his wife - as he appeared onstage at the Rolling Loud Festival at the Banc of California Stadium in Los Angeles on Saturday, December 15.
Offset tried to present his wife with flowers and cake, with the floral display spelling out his plea, "Take Me Back Cardi."
However, in video obtained by Variety, Cardi is seen furiously talking to her estranged husband - and the father of their baby daughter, Kulture - before he exits the stage and his lovelorn flowers are removed.
While Offset's floral signs were being rolled out, the DJ was heard telling the crowd, "Make some noise," before a desperate Offset took the stage to a mixture of cheers and boos.
"I just wanna tell you I'm sorry," he began. "In person, in front of the world. Whatever I gotta do to show you I love you."
The crowd began booing again, as the infuriated "Bodak Yellow" hitmaker can be seen talking to her estranged husband, pointing her finger, and shaking her head.
When the Migos rapper finally leaves the stage, the crowd cheer and chant for the "I Like It" hitmaker as the crew members roll Offset's floral signs back off the stage.
After the gig, Cardi did not acknowledge the incident, but asked her followers in a video on Instagram to stop directing hate at her estranged husband.
"I'm not saying I'm going to get back together with him, but I just don't like that online bashing... that's a nasty feeling. I know how painful it is having millions of people bashing you every day," she explained.
The 26-year-old rapper announced earlier this month that she and Offset had ended their relationship, after more than a year of marriage, amid rumours of the Migos star's alleged infidelity.