Yhombi-Opango died in a Paris hospital on Monday, his family confirmed to AFP.
His son told the news agency that Yhombi-Opango was ill before he contracted the virus.
Yhombi-Opango, who was an army officer who rose to power after the assassination of President Marien Ngouabi, led Congo-Brazzaville from 1977 until he was removed from power in 1979, with the country’s current leader, Denis Sassou Nguesso taking over.
In 1987, he was jailed for three years after he was accused of participating in a plot to overthrow Sassou Nguesso.
After his release from prison, he founded the Rally for Democracy and Development (RDD) party but lost in a 1992 presidential election.
In 1994, Yhombi-Opango became the prime minister but fled into exile in France when the civil war broke out in Congo in 1997.