As conflicting reports suggest Mrs Mugabe has fled the country, Sky News takes a look at the first lady referred to as a “mad woman” and “Gucci Grace” by critics.
Born in South Africa in 1965, Grace Mugabe married an air force pilot and had one son.
In the early 1990s, she secured a job in Mr Mugabe’s typing pool and started a relationship with the President while he was still married to his first wife Sally.
The couple tied the knot in what local press called the “wedding of the century” in 1996.
The Mugabes – who are 41 years apart – have two sons and a daughter together.
Mrs Mugabe ‘s extravagant spending has earned her the nickname of “Gucci Grace” and “First Shopper”, and raised eyebrows across impoverished Zimbabwe.
Known for her expensive tastes, the first lady was reported to have splashed out £75,000 during a trip to Paris in 2002.
She is also said to have spent millions on properties in South Africa, including £4m on a mansion in an exclusive suburb of Johannesburg.
Adverts for the four bedroom home said it had “rolling lawns, a summer house, koi pond and six reception rooms”.
Mrs Mugabe’s first son, Russell Goreraza, has also been criticised for his high spending.
Last month, he imported two Rolls Royce limousines into Harare and was said to be expecting the delivery of an Aston Martin.
The combined value of the vehicles was £4m, Zimbabwean media reported.
The President’s rock
Grace Mugabe has been her husband’s biggest supporter and insists he can continue to rule for years to come.
In February, she even suggested the President could run “as a corpse” if he died before next year’s election.
While Mrs Mugabe has portrayed herself as a fiercely loyal subject, she has also asserted her credentials to succeed the President.
At a rally in 2014, she said: “They say I want to be president. Why not? Am I not a Zimbabwean?”
Meanwhile, last year she reportedly told the women’s league of ruling party ZANU-PF that she was already the president.
Rise to prominence
The first lady is a prominent member of ZANU-PF’s G40 faction – so named as many of its members are in their 40s and 50s and too young to have participated in Zimbabwe’s independence war.
But while Mrs Mugabe is popular with young ZANU-PF members, many of the party’s old guard distrust her intentions.
The first lady has been embroiled in a long-running feud with ousted vice president Emmerson Mnangagwa, who she is expected to replace at a party conference next month.
Last week, the head of Zimbabwe’s war veterans’ group described Mrs Mugabe as a “mad woman” who had come to power through a “coup…by marriage certificate”.
In August, a South African model claimed she was attacked by Mrs Mugabe while she was visiting the first lady’s sons, Chatunga and Robert Junior, in a Johannesburg hotel room.
Gabriella Engels, 20, said Mrs Mugabe’s bodyguards stood and watched as the first lady hit her with an extension cord.
The model suffered cuts on her head and filed an assault charge against Mrs Mugabe, who was allowed to return to Zimbabwe after South Africa granted her diplomatic immunity.
Later, Mrs Mugabe painted herself as the victim of the incident and accused Ms Engels of being “intoxicated and unhinged” and attacking her with a knife.