His death was confirmed by his former Sodelpa party. Mr Qarase had been admitted to a Suva hospital two days ago.
The former civil servant turned politician led Fiji in the wake of George Speight's 2000 coup, and led Fiji through a tumultous period marked by broad economic liberalisation, marked by a series of constitutional controversies.
But after a lengthy and bitter falling out, then military commander Frank Bainimarama overthrew Mr Qarase in the 2006 coup.
