The 31-year-old model shared the sneak peek of the moment with fans on social media joking, "Yes, I do my own stunts."
In the video, Teigen is seen hanging upside down from the rafters, wearing the superhero's red and blue costume.
After host LL Cool J removes Teigen's mask, she says, "I just wanted to see if it's possible that I live out one of my biggest fantasies."
Legend, 38, then appears from backstage and saunters over to his wife of three years. He grabs her face and kisses her.