The 31-year-old 'Girl on Fire' hitmaker, whose charity assists those affected by HIV and AIDS in Africa and India - paid tribute to the talk show host at the annual event at the Apollo Theater in New York, reported BBC online.
"It's a universal truth, Oprah makes change happen," Keys said.
Winfrey replied, "You try to keep a child alive and I try to educate them as best as I can."
Before Winfrey took to the stage, a video played on screen explaining the launch of The Oprah Winfrey Leadership Academy for Girls in South Africa and also detailing the 58-year-old star's own struggles travelling with maids from the inner city out to the suburbs to attend a better high school.
The evening boasted performances from stars including Jennifer Hudson, Bonnie Raitt and Brittany Howard of Alabama Shakes, as well as an auction hosted by Whoopi Goldberg.