The elder statesman, who had just returned from from New Zealand, where he was treated for a stroke he had suffered in 2001, died in a government hospital in Suva.
The country's first and longest serving Prime Minister after it won independence from Britain in 1970, Ratu Mara was a key player in South Pacific politics for decades. After serving as prime minister for more than 20 years, he went on to become the president, finally retiring from public life after the nationalist coup in May 2000.
The nationalist rebels accused him of conspiring with some native chiefs and ethnic Indian businessmen to sideline ethnic Fijians.
"We have lost a giant among men.For as long as many of us could remember, he dominated our national life," Fijian Prime Minister Laisenia Qarase told national television. Ratu Mara was "the father of our nation," and would be accorded a state funeral, he said.