Ironically most of the money will go to a foundation run by the world’s richest man, Microsoft founder Bill Gates.
Mr Buffest said in a statement that he would act on pledges sent to Gates and other foundations to start transferring shares in his Berkshire Hathaway conglomerate to them from July.
Mr Buffet outlined the motivation for his gesture in an interview with
Fortune magazine, which said the handouts would totla about 85 per cent of his wealth.
"I know what I want to do," he was quoted as saying, "and it makes sense to get going."
Mr Buffett said there were no immediate concerns about his health and that he is still "having fun" working in high finance.
"I feel terrific and when I had my last physical, in October, my doctor gave me a clean bill of health," he said.
But he did make a link to the death of his wife, Susan Buffett, in July 2004.
The two had been living apart but remained close, Mr Buffett said: "She and I always assumed that she would inherit my Berkshire stock and be the one who oversaw the distribution of our wealth to society".
Gate foundation to benefit
Mr Buffett, 75, made his billions from astute investments that turned him into a world acclaimed operator.
Virtually all of the money is concentrated in Berkshire Hathaway -whose interests range from insurance to property, energy and jet leasing.
The shares will go to five foundations. But more than 83 per cent of the stock will go to the Bill and Melinda Gates Foundation which already has a kitty of about A$40.94 billion will be used to pay for medical research and give educational grants. Mr Buffett and the Mr Gates' are close friends.
Fortune magazine estimated earlier this year that Mr Buffett has about A$60.05 billion while Mr Gates is now worth A$68.24 billion.
According to Fortune, Mr Buffett plans to eventually become a trustee of the Gates foundation. Bill Gates this month announced plans to withdraw from day-to-day control of Microsoft by July 2008 to concentrate on the foundation.
Mr Buffett said in his statement that the value of the first gift to the Gates foundation would enable it to increase spending by about A$2.05 billion.
"I greatly admire what the Bill and Melinda Gates Foundation
(BMG) is accomplishing and want to materially expand its future capabilities," he said.
Shares will also be given to the Susan Thompson Buffett Foundation, the Howard G Buffett Foundation, Susan A Buffett Foundation and NoVo Foundation (Peter A Buffett) run in the name of his late wife and by other members of his family.
Mr Buffett said he would set aside 10 million shares of class B common stock for the foundation, and award five per cent of the balance of those shares once a year.
Mr Buffett's wife died of a stroke at the age of 72 and he said that his wife had always wanted to give away their money faster.
"I always had the idea that philanthropy was important today but would be equally important in one year, 10 years, 20 years and the future generally."
Mr Buffett said he did not think the gifts would harm the value of Berkshire Hathaway stock.
"I would not be making the gifts if they would in any way harm Berkshire's shareholders. And they won't," he promised.