Raising her arms and jumping up and down when Matt Damon announced that she had won in a category that included Julia Roberts, Oprah Winfrey and Jennifer Lawrence, the 30-year-old said "being recognized by fellow actors is an honor of the highest order," but it's unlikely that the award is going to go to her head anytime soon.
"I want to thank my family who have kept it real," said Nyong'o, who makes her American film debut as a slave named Patsey in 12 Years a Slave.
"My dad, he was the first person I called when I got this role," she admitted. "I said, 'Daddy, do you know Brad Pitt? I'm going to be in a movie with him.' "
"I don't know him personally," her father, who is a Kenyan politician, replied, "but I'm glad you've got a job."
"So am I," she responded. "So am I."
Much More on the 2014 SAG Awards
Can't get enough of Red Carpet Season? Be one of the first to get news on all the awards shows! Sign up below for our newsletter – so you'll be in the know about the winners, the best speeches and the most fabulous fashions.