The Hidden Figures and Empire actress wore a semi-sheer, rose chiffon beaded Reem Acra ballgown.
"I feel like a Barbie doll!" the actress joked to E! News' Giuliana Rancic while posing.
"People keep stepping on it," she said. "That kind of dress, you have to prepare yourself mentally, like 'Get off my train!'"
Henson and the rest of the cast of Hidden Figures are nominated for a SAG Award for Outstanding Performance by a Cast in a Motion Picture.
The movie is about a group of African-American women who provided NASA with mathematical data needed to launch its first successful space missions. The movie was also nominated for three Oscars, including Best Picture.
"I think this movie is bigger than myself," Henson told Rancic. "I think this movie is bigger than any award show. Not to diminish the greatness of award shows, but it's just so much bigger than us all. It's a story about unity, about when we're in our worst of times, how we can come together and get on the right side of history. So it's a reminder of what we need to do right now, today."
"I don't want another young girl thinking that math and science is not for her. And usually, you find that in places where schools are failing," she said, adding, "This movie, I believe, is a movement."