He died after battling ill health, his family confirmed to the BBC. Mr Mugabe had been in hospital in Singapore since April.
He was ousted from power in a military coup in November 2017, ending his three-decade reign.
He won Zimbabwe’s first election after independence, becoming prime minister in 1980. He abolished the office in 1987, becoming president instead.
Zimbabwe’s education secretary Fadzayi Mahere tweeted: “Rest In Peace, Robert Mugabe.”
Mr Mugabe was born on 21 February 1924, in what was then Rhodesia.
He was imprisoned for more than a decade without trial after criticising the government of Rhodesia in 1964.
In 1973, while still in prison, he was chosen as president of the Zimbabwe African National Union (Zanu), of which he was a founding member.