Linda Fuller told that Associated Press that her husband was complaining of chest pains, headache and difficulty swallowing.
"Millard would not want people to mourn his death," she told the AP. "He would be more interested in having people put on a tool belt and build a house for people in need."
Former President Jimmy Carter, called Fuller "one of the most extraordinary people I have ever known.
"He used his remarkable gifts as an entrepreneur for the benefit of millions of needy people around the world by providing them with decent housing," Carter said in a statement. "As the founder of Habitat for Humanity and later the Fuller Center, he was an inspiration to me, other members of our family and an untold number of volunteers who worked side-by-side under his leadership."
Fuller founded the organization in 1976, which has built 300,000 houses for more than 1.5 million people. In 1996, he was awarded the Presidential Medal of Freedom, the nation's highest civilian honor.
However, the organization went through turmoil amid allegations that Fuller had harassed women on staff. Fuller denied the charges, but the board ousted him after he spoke publicly about the matter.
After he left Habitat, Fuller founded the Fuller Center for Housing.
Funeral services are scheduled for tomorrow, and he will be buried at Koinonia Farm in Georgia.
Previous articles on Fuller and Habitat for Humanity include the following:
Questions Follow Fuller's Firing from Habitat for Humanity | Changing corporate culture, not harassment allegations, reportedly led to founder's dismissal as president. But some say the leadership battle isn't over. (February 7, 2005)
How to Build Homes Without Putting Up Walls | Habitat for Humanity strives to keep its Christian identity - a tricky task, when everybody wants to join. (May 31, 2002)
God's Contractor | How Habitat for Humanity's Millard Fuller persuaded corporate America to do kingdom work. (June 14, 1999)
Habitat Builds 50,000th Home | Habitat for Humanity had its busiest week ever starting September 8, constructing 150 homes in 70 cities. (October 26, 1998)
Building Straw Houses on a Firm Foundation | Habitat for Humanity goes low-tech with big results. (February 3, 1997)