The technology colossus's president told Fortune magazine in an interview published Friday that he wants to leave the world in better shape than it is now.
"You want to be the pebble in the pond that creates the ripple for change," Cook told the magazine.
He said ensuring a better world for his 10-year-old nephew was a major factor in his decision. So he will provide for his education, but the remainder of his fortune, which based on Apple's latest stock price is almost $1 billion, will go to various philanthropic projects.
Cook is the latest billionaire to follow a growing trend towards charity, which seems to have been sparked by Bill Gates's announcement a half-decade ago to have his vast personal fortune be spent on charitable pursuits. He was later joined by his closer personal friend Warren Buffett, who has already pledged virtually his entire personal fortune to the Bill and Melinda Gates Foundation.
It's not the first time that Cook has made headlines in recent months for leadership on a social issue. Last fall, he came out of the closet as gay, a significant benchmark for a corporate America that is still very conservative in many ways.
He remains the only out gay person to lead a Fortune 500 company.