Before performing at the annual Global Citizen Festival in New York City on Saturday night, the 67-year-old music legend took the stage and then took a knee, mimicking a gesture of protest first used by Kaepernick, a former San Francisco 49er quarterback, during national anthems.
"Tonight, I'm taking a knee for America," Wonder said to the audience.
"But not just one knee, I'm taking both knees, both knees in prayer for our planet, our future, our leaders of the world and our globe. Amen."
Wonder is the latest celebrity figure to show his solidarity with Kaepernick. President Donald Trump on Friday took aim at Kaepernick's kneeling protest when he called for National Football League fans to boycott games if a player does not participate in the national anthem. He also called for NFL team owners to fire any player who protests during the games.
Trump doubled down on those attacks Saturday when he suggested on Twitter that professional athletes who have "the privilege of making millions of dollars in the NFL or other leagues" should not be allowed to exercise their constitutional right to protest.
Hours earlier on Twitter, the president rescinded NBA star Stephen Curry's invitation to the White House after Curry revealed he would not be accepting it.
Trump's tweets, and his apparently new focus on black professional athletes, caused a roar of reactions from the sports world.
Commissioners for both the NBA and the NFL expressed their disappointment in Trump's rhetoric against the protesting athletes, while many team owners, coaches and players celebrated Kaepernick and the right to take a stand against racial injustice.
Before performing at the Global Citizen Festival, an annual show that encourages ticket holders to engage in philanthropy that will better the world, Wonder made a call for unity and encouraged people to "stand down bigotry," "condemn sexism" and "find love," according to Deadline.
"It is only through life we can make life happen through ourselves and each other." Wonder said to the crowd. "Our global brothers and sisters, I didn't come here to preach, but I'm telling you, our spirits must be in the right place all the time."