The Nelson Mandela Foundation announced the upcoming speech on Monday, saying Obama's address contains the theme "Reclaiming Democracy."
Nelson Mandela Foundation CEO Sello Hatang said the theme was developed to recognize the death of Winnie Madikizela-Mandela.
"This year we thought: who can best represent the legacy of Madiba than the person whom we believe took on the baton when he became president of his own country," Hatang said.
"Who can respond to the challenge? We then kept on asking ourselves who would be able to deal with issues of democracy in a world that is ravaged by corruption‚ and it is the very thing that he was trying to fight against."
The July 17 speech at the Ellis Park Arena in South Africa is expected to be attended by 4,000 people, one day before Nelson Mandela International Day.
Previous leaders and global figures who have delivered the speech include former U.S. President Bill Clinton, Nobel Laureate Kofi Annan and Microsoft creator Bill Gates. All former speakers have been invited to attend the speech.
Obama will also convene 200 young people in Johannesburg for five days of meetings, workshops and technical training.
"It gives him an opportunity to lift up a message of tolerance, inclusivity and democracy at a time when there are obviously challenges to Mandela's legacy around the world," former Obama speech writer Ben Rhodes told The New York Times.
"Mandela endured far darker times than anything we're enduring today."