The 31-year-old model smooched Legend on Sunday's episode of Lip Sync Battle while dressed as Spider-Man and suspended upside down from the ceiling.
"Yes, I do my own stunts," she captioned a clip of the moment for her 5.29 million Twitter followers.
Teigen, who co-hosts Lip Sync Battle with LL Cool J, surprised the audience by descending from the ceiling after Tom Holland's final performance. Holland's competitor, Zendaya, was all smiles as LL Cool J unmasked the model.
"I just wanted to see if it's possible that I live out one of my biggest fantasies," Teigen explained before Legend came onstage.
Tobey Maguire and Kirsten Dunst shared a similar kiss as Spider-Man and Mary Jane Watson in the 2002 movie Spider-Man. Holland and Zendaya star in the new reboot Spider-Man: Homecoming, which opens July 7.
Teigen and Legend married in Como, Italy, in 2013, and welcomed their first child, daughter Luna, in April 2016. The model shared an adorable video of Luna responding to seeing Legend's TIME 100 cover in April.