Lisa Kishkin passed away in a Beijing hospital surrounded by members of her family, relatives told AFP.
She was born in 1914 into an aristocratic Russian family. She studied French and later married Li Lisan, Mao Zedong's predecessor as leader of the Chinese Communist Party, who later fell out of favour and was officially said to have committed suicide.
The two met in Moscow in the 1930s, where Li had been summoned by Joseph Stalin for "self-criticism" for not obeying orders in the Soviet-backed Communist movement.
He was freed in 1940, reportedly at the intervention of Zhou Enlai, who later became China's premier.
Li returned to China, where Kishkin joined him in 1946. Three years later the Communists took power after winning China's civil war.
Kishkin attended Mao's historic declaration of the People's Republic of China in October 1949 as her husband stood beside the Great Helmsman -- though his image was erased from official photos after he fell from grace.
Mao appointed Li labour minister but dismissed him soon afterwards, while Kishkin worked as an interpreter for French delegations visiting Beijing.
Li disappeared in the turmoil, and official records say he committed suicide in 1967 -- a version of events Kishkin heatedly contested.
Kishkin, known as "Lisha", was jailed herself, held in solitary confinement for eight years until 1975. But she was rehabilitated five years after her release by then leader Deng Xiaoping.
Later she was appointed to the Chinese People's Political Consultative Conference, an advisory body.
The then French ambassador to Beijing Sylvie Bermann called her a "living emblem of resistance to extraordinary forces that throughout the 20th century sought relentlessly to deny the sacredness and dignity of the human being".