Born in Johannesburg in South Africa's Indian community, Frene Ginwala studied law in Britain.
The constitutional expert passed away at her home on Thursday night after suffering a stroke two weeks ago.
"Today we mourn the passing of a formidable patriot," President Cyril Ramaphosa said in a statement.
"We have lost another giant among a special generation of leaders to whom we owe our freedom and to whom we owe our commitment to keep building the South Africa to which they devoted their all."
Ginwala's life was changed by the 1960 Sharpeville massacre, when police killed 69 demonstrators protesting against the "pass" laws, a pillar of white minority rule.
She headed for Mozambique, where she helped prominent members of the African National Congress escape abroad after the ANC was banned.
In the 1970s, she became a prominent figure in the international media, travelling around the world to muster support for the anti-apartheid movement and draw attention to abuses.
Ginwala was appointed speaker of the National Assembly in 1994, as Nelson Mandela was elected president marking the end of decades of white rule. She held the post until 2004.
"Many of the rights and material benefits South Africans enjoy today have their origins in the legislative program of the inaugural democratic Parliament under Dr. Ginwala's leadership," said Ramaphosa.