Cabello, 22, and Mendes, 21, made their red carpet debut as a couple at the awards show, which took place in Newark, N.J., on Monday night.
The couple's steamy performance of "Senorita" drove fellow stars wild, with many demanding the pair to kiss.
Cameras caught 29-year-old Swift fanning herself, screaming and leaning into her guests during the performance.
"Game of Thrones" star Turner, 23, was seen screaming at the pair to smooch.
Bebe Rexha was spotted screaming "Kiss! Kiss! Kiss!"
Turner's new husband, Joe Jonas, and his brother, Nick, were also on the edge of their seats.
Joe posted a video of the audience reaction to the moment on Instagram after the show, writing, "#VMAs are over, but we’re still waiting for that kiss tho 👀 @camila_cabello @shawnmendes."
The live crowd wasn't the only group who loved Mendes and Cabello together: The pair won the fan-voted Best Collaboration award for "Senorita."